This is probably because windows 7 doesn't ship with an email client and even though I have outlook set as my default email program and all send to email functions work fine. Even tried setting the default email program to windows live and still same issue, avast is trying to access a built in client ala vista/xp and it won't work on win 7. God only know why avast would need to access an enmail program while right click scanning a file or folder in the first place. Can you please fix this?
saw similar issue here:
http://www.sevenforums.com/crashes-debugging/30036-false-error-there-no-email-program-associated.html