Hello,
We need more info in order to help you. Such as version of Pegasus Mail being used. There are a large number of threads dealing with AVG8 in this community, mostly dealing with being unable to virus scan attachments. But for now, do you have a virus vault with a total size greater than 5 megabytes? AVG 8 puts files in the quarentine folder until the limit (user settable) is exceeded then it just silently deletes them.
Martin