David Lemson's WebLog : Exchange

TechEd Day 1&2 from an Exchange perspective

dlemson — Wed, 08 Jun 2005 13:31:00 GMT

It’s been a huge couple of days for the Exchange team, especially the Exchange Mobile Sync team, which is in my group. In case you missed the news, at TechEd on Monday we announced Exchange 2003 Service Pack 2 as well as the Messaging and Security Feature Pack for Windows Mobile 5. It’s so exciting to be able to show the world what we’ve been doing lately. The summary of what this does for mobile sync devices that use Exchange ActiveSync is to give the end user instant email and the mail administrator the ability to set policies to secure devices. There are some other features for both, including a GAL lookup feature on the device, so you can call, email, or look up office locations of people who aren’t in your contacts. Be sure to read the Exchange team blog this week, where developers from the Exchange Mobile Sync team are writing great, candid, deeply technical articles about our sync changes. (You gotta love Sami's post from yesterday - he was the lead dev for our new "Direct Push" technology)

Last week while the marketing team was working on press releases, press calls, and stuff like that, my PM team and our colleagues in Windows Mobile have been working on the demos that showed off the product on Monday. We had four separate demos on Monday in which we showcased our new mobile features. We had the Steve Ballmer keynote, the Dave Thompson/Kurt DelBene Collaboration Strategic Briefing, the Dave Thompson MSG200 “Exchange Today & Tomorrow” session, and Max Ciccotosto’s SP2 Mobile features session. What a production – we had to make multiple copies of our demo setup and make sure it worked in every room, around the convention center. This is my first time being involved in executive sessions, much less actually doing the demos in one (I did the SP2 demos in MSG200). It involves many slide reviews, runthroughs, and rehearsals. When you see demos go off without a hitch in a big session, you can rest assured that it is because the staff spent tens or hundreds of hours preparing – pre-release software doesn’t just work perfectly by accident!

We also had to cope with handing off a limited number of the cool new devices that we are showing off, like the HTC Universal. It was neat to get to use the Universal – it is a really hot device. The 640x480 screen really makes it look great, and the keyboard is really nice. I can’t wait until I get more time to use one. If you are at the show, make sure to stop by the Windows Mobile booth in the exhibit hall – we have all of the latest Windows Mobile 5 devices on display, including the Universal and the new ruggedized Symbol device shown in the Steve Ballmer keynote.

I also spent some time yesterday in the Exchange "cabana" - a new idea they started at last year's TechEd, where we basically have 10-20 Exchange experts standing/sitting around in one spot all day, waiting to answer customers' questions. I think it's a great thing, and it seems to be well received by attendees. Sometimes I can't believe that we used to just have one evening event of "Ask the Experts" - it's obvious that we're learning and tuning the conference to respond to attendees' wishes.

It's always fascinating to me to see what the "buzz" is in the questions that people have. Of course many of the questions are sort of "the system is doing something it shouldn't, why is that?" which is usually met with a "I have never heard of such behavior, the best way to diagnose that is to call support". We always feel bad when we can't figure something out (as we are driven engineers who take pride in our product!) but sometimes it's hard to diagnose it without seeing the system. People open up their laptops with a terminal services session in to their server, and yesterday I suggested to a guy who works at a bank that he have someone back at the office take a screenshot of his settings and email it to him so he could print it out and bring it over :-). But the most interesting questions are sort of more architectural, "I have this system and I want to change it in this way". It is these questions that allow me to take a "pulse" of the customer base... in 2002, most of those questions were still 5.5 problems from customers who weren't really motivated to move off of 5.5. But in 2003, that started to change, and by TechEd 2004, most of the architectural questions were "I am planning my migration from 5.5 to 2003. Help me make sure I'm doing it right". And that continued in this show - lots of people asking that question (although less than last year, indicating that many of them succeeded).

Finally, the last change that I've seen in this year's TechEd that I applaud is the Birds of a Feather (BoF) sessions being more prominently advertised - actually advertised in the mini-booklet that everyone carries. These have always been the most useful for part of many non-MS conferences, e.g. USENIX events, for me, over the years. Just as you often learn more from your peers that you work with than your managers, I think that you may learn more from your peers at a conference than the sometimes-narrowly-focused experts who give the sessions. How do you think we did with BoFs for the Exchange community?

Want to work on mobile/web access technologies in the Exchange Team?

dlemson — Thu, 03 Feb 2005 18:33:00 GMT

See my post on the Exchange Blog for details on some job openings in my team. As a bonus, can you guess who I am channeling in the first paragraph? (hint: there's a lot of rhetorical questions)

HELLOMOTO

dlemson — Tue, 30 Nov 2004 01:59:00 GMT

Today, our second Exchange ActiveSync licensee announced their upcoming device with direct Exchange Server connectivity: Motorola and their upcoming A780. Of course Motorola has several Windows Mobile devices (the now-shipping MPX 220 and upcoming MPx) which, like all Windows Mobile devices, can also connect directly to Exchange Server, but the A780 is remarkable because it is using a Motorola-customized OS and will have the ActiveSync capability.

Treo 650 and Exchange ActiveSync

dlemson — Sun, 31 Oct 2004 05:12:00 GMT

I am sorely overdue in posting, and I apologize about that. I will hide behind the sorry excuse that the vast majority of what I do nowadays is work on an upcoming release of Exchange that we aren't talking about yet, so I feel like I can't blog all that much about my current work. But last week we had an exciting piece of news hit the world: we have licensed the Exchange ActiveSync protocol to palmOne and the new Treo 650 phone includes it in its VersaMail application. This means that every Treo 650 phone, out of the box with no extra software, can be configured to sync email and calendar directly from an Exchange 2003 server. This is super cool!

You can read a lot more about this feature on the palmOne web site: http://www.palmone.com/us/products/smartphones/treo650/activesync.epl

This announcement was made at CTIA Wireless last week, and there were a whole slough of other Windows Mobile device announcements as well, including several carriers announcing they will be carrying the "Blue Angel" device in the US. This is a great device because it combines the full screen size of the current XDA/MDA/ T-Mobile Pocket PC Phone Edition with a keyboard that slides open when you need to use it.

The RFC 2821 "Covenant"

dlemson — Sat, 03 Jul 2004 06:07:00 GMT

In a recent comment, Mark Hicks asks:

Is there a way to accept a message for an invlaid recipient and then delete it without generating an NDR to the (usually fake) sender? I still want to generate an NDR for my internal users when mail cannot be delivered to an external recipient. -Thanks.

No, Mark, Exchange doesn't have that built in. And while as a mail administrator, in certain circumstances, I can see why you might want to do that, in general that would be a feature that would let people “shoot themselves in the foot”. The reason is that this would break a fundamental rule in the way that Internet mail works. Quoting from RFC 2821, Section 3.7 - Relaying:

If an SMTP server has accepted the task of relaying the mail and
later finds that the destination is incorrect or that the mail cannot
be delivered for some other reason, then it MUST construct an
"undeliverable mail" notification message and send it to the
originator of the undeliverable mail (as indicated by the reverse-
path).

Put a lot more simply: imagine your grandma was sending you a mail. Instead of markhicks@hostname.com, she accidentally typed markhixks@hostname.com. It gets to the right host, and with your request, that mail would just disappear. RFC 2821 requires that your grandma get an error message telling her that her mail didn't get through. Either your server, or the machine that was trying to submit the message to you, needs to create that error notification. Now, whether or not the error message is formatted so bizarrely such that your grandma has a hope in understanding that reason is another thing... but at least she's going to call you and ask you why you're refusing her mail!

Incidentally, the next line of that RFC is interesting for Exchange 5.5 aficionados:

Formats specified for non-delivery reports by other standards
(see, for example, [24, 25]) SHOULD be used if possible.

For reference, [24] is RFC 1891 and [25] is RFC 1894. When Exchange 5.5 was the most prevalent version of Exchange out there, we got a fair amount of heat for the fact that Exchange 5.5 does not generate RFC 1894-compliant non-delivery reports, although it does support RFC 1891. I won't debate whether or not that was the right thing to do, but I will point out that SHOULD in there. Of course, we did support RFC 1894 reports fully starting in Windows 2000 SMTP / Exchange 2000, so we're all good now. And, finally, I am proud of the fact that Exchange users who use Outlook or Outlook Web Access don't have to see the potentially-confusing format of RFC 1894 notifications, we have a nice readable non-delivery report error form, which in Outlook includes a “send again” button, which is mighty handy.

Blogging from TechEd: Exchange SP1 and IMF released

dlemson — Tue, 25 May 2004 14:30:00 GMT

I'm sure you've read it elsewhere, but here's one more link. It was hard to sit on this as people were commenting their lament over not being able to get IMF, but trust me, it's worth the wait. You can find both SP1 and IMF linked off of http://www.microsoft.com/exchange, and here's the IMF directly: http://www.microsoft.com/exchange/downloads/2003/imf/default.asp.

Elsewhere at TechEd, the weather in San Diego makes the mood good. The convention center is huge and thus makes the crowds seem not so big, because there is a lot of room for people to spread out. We have a new concept this year called “cabanas” and it gives people a place to drop in, hang out, meet experts, and talk about their favorite topic (in the case of Cabana 10, it's Exchange!). They're encouraging speakers to spend all of their free time there, so you can always find 5 or 10 Exchange product group team members there. Drop by, I'll be there most of the day Tuesday and Wednesday (except during Dave Thompson's keynote on Tuesday morning, where they'll formally announce IMF release).

Exchange Development at TechEd

dlemson — Wed, 19 May 2004 06:46:00 GMT

What have I been spending my time on this week? Polishing my presentation on Exchange Development! I'm presenting a MSG330:Exchange Development at TechEd San Diego this year, 5:30 pm Wednesday, room 32AB for those of you who are attending. Many of you have no doubt seen Mindy Martin give a presentation with the same name in years past. While I did start with her presentation and demos, I promise you that you will see new content and new demos! (well, if the demos work, but isn't that always the case?) If you have any areas you want to make sure I cover, now is the time to comment here or send me mail. There may be time to squeeze a slide or two in if I wasn't already planning to talk about it.

And, here's a chance to plug your favorite Exchange development-related web site. I have a few slides of links at the end and I am always looking for more gems to reference. Help your fellow Exchange developers by listing great sites and I'll put them in the deck. (and we'll make sure they're linked off of the Exchange web sites too)

IMF settings

dlemson — Wed, 05 May 2004 03:34:00 GMT

Several people have commented or emailed me asking me for my IMF settings, since I mentioned that I am using the IMF on my personal mail server. There are basically three settings for IMF:

The Spam Confidence Level threshold for acting at the gateway, as part of the SMTP conversation
What to do if you act on the message at the gateway (reject, accept and archive, or accept and delete)
The Spam Confidence Level threshold for putting messages into a user's Junk Mail folder

If you have acquired IMF, hopefully you looked at the documentation, which tells you about the performance counters that you can use to look at how many messages the IMF has classified into each bucket. The best way to determine what your threshold should be is to run the IMF on your normal mail load and look at how many messages fall into each bucket (1-9). 9 is the messages most likely to be spam, 1 is the messages least likely to be spam.

Now, on to actually answering the question: I run 8 as the threshold to reject at the gateway, and 4 as the threshold to put messages into the Junk Mail folder. I have noticed a few false positives at this level, but for me it's acceptable and I look at the junk mail folder periodically. I get about 50 messages in my junk mail folder per day, with an average of 0.25 false positive per day. I get an average of 2 false negative (spam that makes it into my inbox) per day. This is vastly superior to what I was getting with Spamassassin before I switched my mail to Exchange 2003 several months ago. I run 4 as the junk mail folder threshold because I really get very little important mail to this domain, so I would rather err on the side of putting things into the junk mail folder.

Note: other spam marking software may use different criteria to set the SCL, so these numbers are only valid for the Microsoft IMF.

ResolveP2, RerouteViaStore, and its equivalent in Exchange 2003

dlemson — Sun, 28 Mar 2004 04:35:00 GMT

Recently I have encounted a number of people who asked what the ResolveP2 reg key in Exchange 5.5 was meant for, and how to emulate it in Exchange 2003.

ResolveP2 in Exchange 5.5

ResolveP2 tells the Exchange server “when the server is storing MIME content, and needs to convert it to MAPI properties, does it try to resolve the SMTP addresses in the RFC 822 fields and turn them into Exchange Distinguished Names (DN)?“ And, you can specify the exact fields that it will resolve because the regkey is a bitfield.

Here's the situation where you'd want to enable and disable this:

Enable: Imagine you have an Exchange user who sends mail to an Internet listserv, and the listserv has other Exchange users as members. When that user sends to the listserv, the mail comes in From: this internal user via SMTP. If you want your internal users to see this mail and be able to double-click on the sender and see the normal Exchange properties of this user, then you must be sure to set the ResolveP2 key to resolve From:. (which is “ADDRESS_CONVERT_SENDER“, so you add “1“ to the value).

Disable: Imagine that you have someone on the Internet sending mail in to your users, pretending to be the CEO of the company. They spoof their From: address to be the CEO's SMTP address. The mail comes in and when the user double clicks on the From: field in Outlook, they see the CEO's details just as though it really came from the CEO. In this case, you would want to set ResolveP2 so that the From: field was not resolved. When it's not resolved, then when they double click on the sender, they will see this three-line dialog that shows the display name, address type, and SMTP address. Outlook 2002 and 2003 do even better because they show this distinction on the From: field without needing to double-click: the name will show up like Bob CEO [bob@company.com], whereas real mail from Bob shows up as “Bob CEO“.

So as you can imagine, different situations will require different settings. In Exchange 4.0, the setting was to resolve all fields by default. For some reason (I do not know the reason exactly), they changed the default in Exchange 5.5 so that no fields were resolved. We found that there were a large number of PSS calls from people who needed to turn on resolution in 5.5. It has occurred to me writing this that the reason is that the KB articles around ResolveP2 are really confusing. I am engaging the right people to get that fixed.

Exchange 2000

In Exchange 2000 SP1, we come up with a similar solution. However it was missing something: ReRouteViaStore.

Adding RerouteViaStore

The above all works great for messages that come in via SMTP and are either locally delivered to a user or goes out via RPC or X.400 via the MTA, because in those cases, the message is saved to the Exchange store and the MIME -> MAPI translation takes place. But if the message comes in via SMTP and goes straight back out via SMTP, then the MIME -> MAPI conversion that I described above would never occur. The solution in Exchange 5.5 was a regkey called RerouteViaStore.

The combination of ResolveP2 + RerouteViaStore helps in the situation where you have two mail systems: company.com and unix.company.com. company.com is the Exchange 5.5 system and accepts all of the mail from the Internet. The users on unix.company.com funnel their mail out through the Exchange system.

Their From: might be From: user@unix.company.com, but you don't want to expose that address on the Internet. So you have a user or contact in the AD for each user on the unix.company.com system, with a secondary address of "smtp:user@unix.company.com" and a primary address of "SMTP:user@company.com". If the mail came in and went out via SMTP, address rewrite will cause the Exchange 5.5 machine to look up the address in the From: (and Reply-To) to find a proxy that matches, and rewrite the address with the primary address on that user or contact. This is also described in a KB article.

Exchange 2003

Exchange 2000 was lacking the RerouteViaStore capability. The only solution in Exchange 2000 was to write a custom transport event sink that modified the headers, which can be tough work to get right. In Exchange 2003, the transport team added RerouteViaStore capability. The way you turn it on is via a special utility that has recently been published to the web called Address Rewrite Config (click to download). Remember that this utility only works with Exchange 2003. What it does is to force messages that come in on an SMTP VS to be committed to the store, so that the MIME -> MAPI translation takes place, which is exactly what RerouteViaStore did. Like RewriteViaStore, this can cause a performance degradation, but depending on your message load, it may not be a big deal. You can imagine the difference between storing the message, untouched, as a MIME stream as a file in the queue directory on disk and then just reading that and sending it out, versus saving to the Exchange store, having it be converted to MAPI properties and then reading it back out of the store, which causes a conversion back from MAPI to MIME.

Sharing a domain between two Exchange orgs

dlemson — Wed, 03 Mar 2004 16:55:00 GMT

Luke asks:

I am in the process of migrating from Exchange 5.5 to Exchange 2003 for a company that has multiple small (less than 5 users) branch offices.

They want to migrate slowly, so here's my dilemma: The current Exchange 5.5 will still be active for a while. I'm using the Exchange Migration Wizard in Exchange 2003 to migrate the mailbox data over.

All incoming mail needs to be split between the two servers, as the new Exchange 2003 server will be gradually hosting more & more of the users.

Can you point me in the right direction where I can learn to write an SMTP event sink to route some recipients to one server, & others to the other? Thanks!

I can't join the Exchange 2003 server to the same Exchange 5.5 site, as it's in a different domain.

Luke, first a question and an assumption. When you say that the Exchange 2003 and Exchange 5.5 servers are in different domains, do you really mean that they're in different AD Forests? That you haven't done anything to join the two together, that you just want to start fresh with a new AD that just has the Exchange 2003 server in it? I'm assuming so. There's no need to write any code to do what you want to do. What you want to do is exactly the same as sharing an SMTP domain between two totally separate Exchange orgs. What you need to do is to make one the “hub” for the domain, where all inbound mail comes in to, and it forwards other mail to the other system. And good news, there's a KB article that tells you how to do it:

XADM: How to Set Up Centralized SMTP Domain Sharing in Exchange 2000 Server for Independent Organizations

How are you using the Windows 2003 POP Server, Part II

dlemson — Tue, 24 Feb 2004 13:59:00 GMT

In a previous post, I asked people how they are using the Win2K3 POP server and what features they wish it had. One thing I'd like to get, especially from people who posted that they do use it today, is some more details on why and how they are using it.

1) It seems to me that a Windows Server license is pretty expensive, so are you buying Windows Server for other reasons and just happen to use the POP server because it's free, or did the POP server play a role in choosing Windows Server? Do you have other dedicated servers already?

2) What kind of scenario are you running it in? Are you an ISP, are you running it for your home/family? Are you running it for a business?

3) What other options did you look at and why did you or did you not settle on using the Windows POP server?

If you would like to send me a response via private mail or feedback, please feel free to do so.

How are you using the Windows 2003 POP3 Server?

dlemson — Fri, 30 Jan 2004 06:10:00 GMT

I saw a link on the “hellomate“ MS Exchange blog to a post singing the praises of the POP3 Server that comes in Windows Server 2003 and it reminded me that I wanted to write about this and ask people to comment or write, and tell me what you are using the POP3 server for, and how you like it.

For Exchange admins, the POP3 server can be confusing, because the “Manage Your Server” wizard that comes up when you install Windows 2003 offers to let you select the “E-mail server” role for the server, and when you do that, it installs the POP3 service and the SMTP service. Unfortunately, the POP3 service is incompatible with Exchange, so Exchange 2003 setup will tell you to remove the POP service before it allows you to install Exchange.

If you are using the POP3 server, what do you wish it did, and how would it change how you use it? My team is responsible for the future of this service (among other things), so you're getting an opportunity to talk directly to the right person!

More from Michel on customer feedback

dlemson — Thu, 29 Jan 2004 00:22:00 GMT

In a comment to my last post, Michel says:

It sure helps to demystify the process, but also shows there is no direct contact between developers and customers. PSS, a product group or reports form software tools are always 'in the middle'.

I'm sorry that I gave you the impression that there is no direct contact between developers and customers. That could not be farther from the truth. It may be a problem that I didn't define the term “product group“. To us, the “product group“ is the group that designs, engineers, and tests the actual product. It comprises mainly program managers, developers, and testers. So for the most part, developers == product group.

I mentioned validation with some types of customers above (e.g. MVPs), but other ways that developers get direct feedback from customers include:

- Newsgroups and public mailing lists. We have quite a few people from the product groups that lurk and even a few that post regularly to such lists. I've been a member of the exchange2000 yahoogroup since its inception. I also read and sometimes write to a number of other lists, including one for Windows usage in Higher Ed (I used to work in Higher Ed so this is near and dear to my heart) and one for SBS.

- Conferences. When I go to a typical conference for a week such as TechEd or ITForum to speak, I will probably speak directly to 200 customers.

- Blogs! I'm getting direct feedback from a customer right now!

I didn't mean for the previous post to be an exhaustive list of how we get feedback from customers.

How do we decide what features make it in to Exchange?

dlemson — Wed, 28 Jan 2004 07:36:00 GMT

In a recent comment, Michel asks:

How do you come up with a list of new features that are to be included in a new release?

In a 'Meet the Expert' session here in the Netherlands last December, I discussed a problem for which ' the expert' knew a ' feature design request' was already on the list: how did it get there? Not my single PSS call I assume..

Great question. As usual, it's not an easy answer. There are a ton of inputs that go into the list of things that we might include in a given service pack or release. Of course, we strive to include only bug fixes in service packs, but sometimes these features are such a high priority that we must include them in a service pack. Some of the inputs include (in no particular order):

- Customer escalations via PSS (MS Product Support Services for those who are lucky enough not to have needed to call) or Premier support. The term that the Microsoft person used is Design Change Request, or DCR. This is our term for a change to the product after it's been released. It is unlikely, Michel, that your single PSS call resulted in that feature being on the list of things to be done, but when someone asks for a feature through PSS it can result in a “tick mark“ in a database.

- MSWISH. This is a way that anyone can make a product enhancement suggestion, without needing to call PSS or have a support contract. The URL is http://www.microsoft.com/mswish. You can fill out a web form there, or send email directly to mswish@microsoft.com. All of these entries do go into a database that ends up at the appropriate product group. This isn't just for Exchange.

- Product Group brainstorming. We may have a developer, tester, or program manager who comes up with an idea and champions it. They will typically solicit customer feedback, and fight for the “ticks in the database” that will get it done. They may also harvest data from PSS call logs to see who called in with a problem that would have been solved with that fix. They may communicate via email with our MVPs (Most Valuable Professionals) to ask their opinion: have they seen a lot of this on the newsgroups, does this sound like a good idea.

- PSS feedback. PSS classifies customer calls, and they keep track of the types of problems that cause the most customer calls. Then they give that feedback directly to us in the product team. They say “if you were to make this easier, then these people wouldn't have had to call“. That's an incredibly powerful tool because it shows you exactly which things you can fix or improve that will result in a direct improvement in customer satisfaction. Because after all, no one wants to call PSS. (even though they are very nice to talk to)

- Microsoft Customer Experience Improvement Program Data. The CEIP is a fairly new tool that we have introduced in a number of products, including MSN, Messenger, Windows Media Player, and Office. For those customers who opt-in to send us their anonymous usage statistics, we can see a picture of their experience using the software. We don't capture data from their files, but rather how the program is being used. As a hypothetical example that I just made up, let's say that we saw that a huge number of people using Outlook go into Tools -> Options... -> “Other“ Tab -> Advanced Options... -> Reminder Options and turned off “Play reminder sound“. We might make the default be to not have a reminder sound in the next release. Or we might put that setting in a more prominent place. You can see the potential. We also use this to look at what kinds of error dialogs people run across. Sometimes we aren't sure how often a particular error will be hit in the real world. If we see that something is hit often, we might be able to put code in place to prevent that condition from occurring in the first place. It helps us know where to spend our time to know what will be the biggest bang for the buck for the customer.

Now I have talked about these “ticks in the database” - these are virtual ticks, there is no set threshold after which a particular feature will get done. The amount of proven demand necessary to do a particular feature will vary greatly depending on the difficulty of the work. For example, if something needs work done in Exchange as well as a change in Outlook, you can imagine that it takes a lot more persuasion and customer data to get that done. Once the decision is made to do a DCR, then we decide what is the most appropriate release. Do we need to correlate it with an Office release, etc. Sometimes, unfortunately, as we start to do the coding or test the feature, we find that it didn't work the way we initially expected or it was more complicated, and we have to re-think the feature. This is one reason that we don't like to discuss upcoming features until the product is very close to being released: you never know when something will need to be cut because of unforseen circumstances.

I hope that demystifies the process a little bit.

HP Exchange 2003 Academies

dlemson — Tue, 20 Jan 2004 00:24:00 GMT

HP is starting a new round of Exchange 2003 Customer Academies and I wanted to give them some press, because I think they are a great way for customers to get deep knowledge about Exchange. I was involved in the development of the first (then Compaq) Exchange 2000 Academy in 1999, and have known the HP Services people involved for several years. They “test“ these academies by giving them to internal HP Services consultants first, and once they have the bugs worked out, they offer them to customers. The HP services people involved are all some of the most expert people on Exchange outside of Microsoft, and I highly recommend going to these so you can pick their brains. Plus, it's pretty fun to party with them.

The two coming up are:

Heathrow, London, UK February 8-13 2004: http://clmuk.europe.hp.com/emauk/www/q104/exchangeacad/academy_home.jsp
Orlando, Florida USA March 15-19 2004: http://clmuk.europe.hp.com/emauk/www/q104/exchangeacad/academy_home.jsp

Disclaimer: the experts in question have given me various dinners, bottles of French wine, rounds of drinks, etc. over the years but I assure you that I recommend them solely on their technical merit.