Over the last few months, as I ran up towards my 30gbs of gmail storage, I started to notice problems with sending messages, specifically, with attachments (error while running message filters), they weren't auto saving, but the problem was intermittent (and the messages were always sent). However, I recently upgraded to 100 gbs of gmail storage (and have around 60k emails in Thunderbird), and now, every time I send a message, I end up with the picture below, i.e. it hangs on 'Copying message to Sent Mail Folder.' Message still sends fine. I then have to: 1) Click cancel 2) Select from Retry/Save/Don't Save (Your message was sent but a copy was not placed in your sent folder due to network or file access errors 3) Click ok (error while running message filters on it) 4) Click ok (another Alert - error running message filters on it) Obviously, I want to go back to 'normal' and not have to jump through steps 1-4 with each email. Suggestions?