Let's start simple: go into Internet Explorer, choose Tools>Options>Programs and check what it says about your email client. If it isn't Outlook, make it Outlook. If it is Outlook, make it Outlook Express and see what happens; then switch back to Outlook.
There might be other possibilities, but this is the first thing to check.
You must be one of the few people outside Microsoft who know what registry entries to check for this problem. Could you share your knowledge?
I run Office 2003 and Windows XP, and Outlook 2003 for email; all are fully up to date with all the relevant service packs and updates. This week I have noticed that I do not have an email button on my Standard toolbar in Word, and under File, Send To, the "mail recipient" option is greyed out, although the other options to send as attachments are OK and work fine.
I have checked the registry entries and they appear OK; I have checked the win.ini file and that is OK; I have tried going to Run, and typing "regsvr32 sendmail.dll", which has no effect; I've checked my Outlook profile and that's fine; under Word, Help I've done the "detect and repair" option; I've tried reinstalling office (I did not remove Office and do a clean install as that would have lost all my settings).
All of this has made no difference at all. I can email perfectly well from Outlook; I simply can't send an open file by email.
Can anyone out there help?