Greetings, folks! I am fairly new to using an IMAP connection between Thunderbird and the host mail server, HostMonster. There's behavior that I could use your help understanding. First, I can send and receive mail just fine. Basic configuration works. The issue is this: When incoming messages appear in Thunderbird's inbox for the IMAP account, I drag (move) them to an appropriate local folder for archiving. That works fine. The message disappears from the account's inbox and now is in that local folder. If, however, I log in to the hosting company's web email interface (roundcube), and look at the IMAP inbox, the moved messages are still there, but grayed out. They are marked as deleted, but still (in some nebulous state) in the inbox. I can manually select then delete the grayed-out messages, and they go away permanently. If, on the other hand, I select a message in Thunderbird's inbox and delete it, the message disappears from both Thunderbird's IMAP inbox and the web email interface (roundcube) inbox. That's as expected. SO, the question is whether there is a Thunderbird configuration setting that I've missed, which will actually delete the messages from the server's inbox? Thanks very much for your help.