Okay, so part of my myriad job duties is to test out the monthly Patch Tuesday goodies from Microsoft and ensure they don't break anything. This means while everyone at our clients gets to ignore the patches until I give the green light (all automated), me and my partner in crime get to play with them.
She did the initial installation on her system, Win7 64 bit using Office 2010 Professional. One of the patches is apparently corrupting the password/authentication file, and causing Outlook to drop from Exchange in about 30 seconds.
My own testing of installing all 9 of the April patches for Win7 has narrowed this down to KB2553248.
Outlook still functions normally, there is just a bloody pop up Window that says "Windows Security" at the top then "Microsoft Outlook / Connection to (my AD login email address.) The OK button is grayed out, but the cancel button can be clicked.
Clicking the cancel button kills the connection to Exchange. You can reconnect by hitting the "Need Password" bar at the bottom of Exchange.
This only happens to me when Outlook is first started (within 30 seconds) and then once every 15 to 20 minutes. I've googled left and right and found no solution to making this stupid pop up window go away. Since we use auto detect authentication, once we reconnect to Exchange the first time, the connection is never dropped again unless we hit the cancel button.
SO: If you are using Outlook 2010 with a local Exchange server, DO NOT install KB2553248 until Microsoft releases a patch or a solution to this issue, or else you will be as annoyed as I am right now.