I've seen this idea pop up a few times, so here's my contribution to this meme:
When I was in Outlook, I ran a bunch of mail servers for testing in our interoperability lab. At one point I needed access to an HP Openmail server for some testing, and I found out that the Exchange team had one. So I contacted the owner and asked for an account on the server, which he granted. I quickly found out that it wasn't configured to allow email to flow outside of the server, so I asked them to do that. He wasn't sure how to do it offhand and didn't have time to research, so I offered something like “Well, I have experience with UNIX mail servers, perhaps I could take a look and figure it out?”. They agreed, sent me a huge stack of manuals and gave me admin access, cautioning me to be careful.
Being human, I of course went directly to the part of the manual about “accessing the internet via smtp”, assuming that was the right section. I skimmed through the chapter (again, normal activity here, we all know that no one actually reads documentation ;-) and got to a part where it talked about adding an address routing (or something like that - can't remember the exact term, this was 6 years ago). The routing address for internet access was something like “*,*,*”. So I added it, tested it, and nope, it didn't work.
So then I went into the admin program and deleted the address routing that I had just created and was reading through the docs some more when I got a frantic call from a tester on Exchange. Apparently I had deleted the entire server - all of the accounts, mailboxes, etc. Oh boy, egg on my face. But I was also (justifiably IMO!) upset that deleting something I created caused such a catastrophe. To this day I still don't get how that happened, but it was never a priority to research enough into how openmail works to figure it out.
Oooh - how horrifying! And especially, as you said, for something that you created yourself. Very unfair.
The two lessons I'm learning from my many mistakes are:
1) Make a backup!
2) Try it in a VM first!
When I remember one of these two things, I almost always can recover successfully. When I forget, I am sad, sad, sad.
Oh my god !.
This entry remembers to me a "now" funny thing that happen to me when I was working on a migration from cc:Mail to Exchange 5.5 on 1999.
They were using an application called IMA http://www.ima.com that translated SMTP addresses to cc:Mail aliases and acted as email gateway. OK, four days before the end of the year (Dec 26) I did a final research on the product and found that the version that they were running was not Y2K compatible !!!.
I talked to the customer and went to company website and downloaded an updated version for the product and run setup against the server.
Half an hour later I found that because the upgrade, database went replaced with an old version and all the aliase were mixed up and wrong ! (Not really funny).
Finally I have to stay working around 18 hours to reenter all the accounts one by one (2500 +-) and testing them.
Believe me, I learned the lesson.