outlook

Clarifications

Do you send the error report to Microsoft? If so, do they send anything back? These are most frequently caused by some add-in loaded into Outlook, try starting Outlook in safe mode...Start-->Run-->outlook.exe /safe, if it works using this method, restart Outlook in normal mode, then go to the add-in manager and start disabling the add-ins one by one until you figure out which one it is.

has made a mess of something. Try opening Outlook in safe mode (start -- run -- outlook.exe /safe)
if it opens correctly, go to tools -- options -- other (tab) -- advanced -- and disable some add-ins.
Also, acrobat buttons often cause this as well.
If it continues, check to see if Word is your default email editor, if so turn it off. See if the problem continues. If Word is causing the problem, look for add-ins in Word, or reset the normal.doc file.