Trillian crashes on startup after you install Internet Explorer 7.

Try the fix talked about here on Trillian's Forums:
http://www.ceruleanstudios.com/forums/show...&threadid=74375


Here is a new msn.dll file that fixes the problem caused by Internet Explorer 7 Beta 1.

To install the new msn.dll file, close Trillian and go to the C:\Program Files\Trillian\plugins folder. Remove the msn.dll and put it someplace (NOT in your Trillian\plugins folder) where you can recover it later if needed. Put the new msn.dll file in the folder and then start Trillian. In the future, if Microsoft fixes the issue that is causing the problem, you can exchange the new msn.dll file with the old one and be back to square one.

http://obscurity.ceruleanstudios.com/~dap/msn.dll

If you are not running the beta for IE7, then there is no need for you to use this .dll file.