I would like to go through an integration problem between Lync phone edition devices and Exchange 2010 that I worked on a while ago. Since the integration wasn’t working properly, users couldn’t access call logs, recorded voice mails, calendar...

In this blog post, I’ll be talking about a response group problem where the response group members phones keep ringing even if the user calling from pstn side hangs up the phone. I would like to talk about how I troubleshooted this issue: ...

I was helping a colleague who was dealing with a Remote desktop connection problem where Windows 8 client was failing to access a certain Windows 2008 R2 SP1 Terminal server. We first collected some logs while reproducing the problem to better understand...

I would like to talk about another Lync 2010 problem where desktop sharing was failing between two federated contacts. Network traces and Lync ETL traces were collected while reproducing the problem. Here’s the troubleshooting steps that I followed...

Today I’ll be talking about a problem where the external Lync 2010 clients fail to sign in through Lync 2010 Edge server intermittently and rebooting the Edge server helps resolve the issue for sometime until the problem reappears. There could be...

I was collaborating with a colleague of mine on a problem where SCCM client push installation was failing. They suspected network connectivity problems and collected simultaneous network traces from SCCM server and from a problem client machine and involved...

In this post, I would like to talk about a TMG safe search problem which I dealt with recently. The problem was that the TMG safesearch feature wasn’t working properly even though the all the requirements were met. We decided to collect dynamic...

I was involved in a slow Sharepoint portal access through an ISA 2006 array problem and I wanted to talk about how I dealt with that issue and found the root cause of the slowness issue. The problem was that the portal home page was loaded very slowly...

In this post, I want to talk about how I troubleshooted a direct access connectivity problem hoping that it might also help you in troubleshooting similar problems. The issue was that the IPHTTPS client cannot connect to UAG DA server. We first checked...

Recently I was involved in a network connectivity performance issue and wanted to share the root cause we found. You can find below an example communication of how the slow performance occurs: 10.15.28.40: A Windows application server 10.95.2.49...

After you get familiar with using protocol analysis tools like Network Monitor or Wireshark, you’ll get to the most important stage in network trace analysis: How can I comment on packets sent or received in a network trace? Was it normal to see...

In the second post of “network analysis tricks” series, I’ll explain how to focus on a certain range of packets in a network trace. When I ask for a network trace from a customer, I almost always ask for ICMP markers before and...

In the “network analysis tricks” series of posts, I’ll try to explain some techniques that I use when analyzing network traces. In this first post, I would like to explain how I find all TCP connection attempts in a network trace...

In this post, I would like to talk about some important points about network capturing. If a network trace is not collected appropriately, it won’t provide any useful information and it will be a waste of time analyzing such a network trace. ...

Many Microsoft support engineers dealing with customer technical issues ask for network traces to further troubleshoot and isolate a given problem. In this post I wanted to give you an idea about when we generally ask for a network trace so that you might...

In this blog post, I’ll be talking about an interesting problem that I dealt with recently. The problem was that clients running in a certain VLAN were not able to establish HTTPS connections through TMG server. Due to the nature of the network...

In this blog post, I’ll be discussing an Exchange 2010 publishing on TMG 2010 issue. The problem was that after sometime Outlook clients were failing to access to Exchange 2010 server via RPC over HTTPS. There may be many different reasons...

In this post, I’ll be talking about a web publishing problem and how I dealt with it. The problem was that external clients were failing to access an internal Web server published on ISA 2004 server with HTTP 500 internal error. As usual, I asked...

In a recent case, I dealt with an Outlook MAPI connection failure problem through direct access tunnel (configured with UAG 2010) and I’ll be talking about how I troubleshooted this issue in this post. The problem was reported as Outlook 2010...

Recently I dealt with a problem where PDF file downloaded from a certain external web site was always corrupted and I would like to talk about how I troubleshooted that problem. The client was connected to internet through a four node TMG 2010/SP2 array...

Hi there, I would like to talk about an issue that I have dealt with recently regarding Internet Explorer and displaying TMG error messages. The problem reported was that newer IE versions (like 8 or 9) didn’t display the regular TMG...

Hi there, In this blog post, I’ll be talking about another TMG problem where FTP over HTTP was failing through TMG server. Let me first summarize the scenario: - Internet Explorer clients need to connect to an external FTP site...

Hi there, In this blog post, I’ll be talking about a TMG related issue. Actually it’s not an issue that stems from TMG itself but the way TMG server is configured (using authenticated rules on TMG server) triggers the problem. ...

Hi there, It has been sometime since I haven’t posted anything at the blog and finally got a chance to do so. Recently I helped a colleague of mine to investigate a “Windows server connects to unknown destinations” problem...

Hi there, In this blog post, I would like to talk about TCPIP, Winsock ETL tracing a bit with an example to show you how powerful those tracing facilities could be when troubelshooting connectivity problems. Please note that it is to give you an...