I have been having trouble all of a sudden, with my browser connection timing out when emailing large files. Seems like nothing over 5megs will send anymore. This has not bee a prob 'till recently. I have un-installed and re-installed, but still have the prob. Can’t find a time out user setting. Any ideas??
Thanks,
Confused
Welcome to the forums, hd53. 
A search of the forums for … time out … produced many results. The Search button is at the top of the forum page. The result at the link below might help you. Be sure to see the picture in David’s last post.
http://forum.avast.com/index.php?topic=19506.0
I hope this helps you.
Straight from the horses mouth, so to speak ;D
What is your email program ?
It takes time to scan the large attachments, during that delay it may seem to the email program that there is no activity so it throws up the timeout warning (frequently discussed in the forums), so you may need to extend the timeout delay in your email program and possibly in avast also.
Example for OE:
http://img.photobucket.com/albums/v325/for-dwr/timeoutoe.jpg
Timeout setting avast:
http://img.photobucket.com/albums/v325/for-dwr/timeoutav.jpg