This may seem like the obvious, but why don't you uncheck the MS Word so that it is not associated. You said that it worked OK that way. I have 2003 and new messages always open in the Outlook pane unless I double click and then it opens in full pane.
If I do not use Word, which I have done for years, then I don't get the Word spell checker and some other formatting. I know I can uncheck that and it works the way I want and the way it used to work, with Word, but that is not fixing the problem.
I've removed just everything I can see or think would affect it and it hasn't made any difference.
re image all
I've got an Acronis disk backup for 0430 (and a two later backups) but that is a last resort.
After looking at what has been done since the oldest available full hard drive backup, I'm going to have to "live" with the issue until I can find a fix.
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