I have a recurring problem with mail becoming stuck in my Outbox. The symptom is that I discover, after hours of working, sending mail, and receiving mail, that the "sent" mail is all actually stuck in Local Folders Outbox. If I click on Outbox I can see the email messages that are waiting to go out. The only way to get them to go out is to quit Thunderbird and then restart, at which point I can see them go out, one by one. This has happened to me many, many times, but not every day - or even every week. It's hard to pin down what what is causing the problem, but I have a feeling that it is vpn related. My normal mode of operation (on a Macbook Pro) is to switch back and forth between home and work networks (or travel networks) without logging out or quitting tasks (including Thunderbird). I don't think that's the problem. While I am working, I frequently have to switch to an internal vpn to access various things. I don't like to run video conferencing or other high bandwidth tasks through the vpn server, so I generally disconnect when I don't need it. I *think* Thunderbird is sometimes getting confused about the network - perhaps when I've started composing an email with vpn running but switching vpn off before sending. Honestly, though, I think I do that so often that this can't be the core issue. So: Question 1: Has anyone seen this and found a solution? I've tried just writing a cron job that watches the file "Unsent Messages" in /Users/myname/Library/Thunderbird/Profiles/[profilename]/Mail/Local Folders I just check to see if there are messages in there, and send myself a notice. However, this doesn't work because that file doesn't actually seem to empty itself once messages go out. It doesn't save all outgoing mail, but it saves a bunch, so my trick won't work. Question 2: Does anyone know why the Unsent Messages file doesn't clear once the messages go out? Question 3: Is there some other indicator that I can probe to see if there is stuck outgoing mail? Sorry for the long description. I wanted to be as complete as possible. Thanks for any help.