I am also having this problem, and setting both expunge_mode and delete_mode to immediate in `imapd.conf` is not correcting the problem.
What is odd is that messages within the Trash folder *are* being expunged when cyr_expire runs. But the original message remains for example in the INBOX folder on the filesystem, as well as within any folder from which it might have been moved. I've checked annotations for e.g. the Trash folder vs. e.g. INBOX and see no differences (most are set to NIL).
Quite puzzling and something with which I really need help.
I upgraded directly from 2.2 to 3.8.x about two years ago, and the upgrade went smoothly and all operations seemed normal. But now I'm finding that every single move and delete operation has and is leaving behind a trail of unused files on the filesystem.
I also have a client for whom I performed a similar upgrade (from 2.4 I believe) back in March, and their installation is somewhat large with a huge volume of Spam/UCE, so in their case this inability to expunge from the filesystem is rapidly wasting disk space.
Thus, I am most grateful for any assistance. We've plenty of disk space, so there is no rush, but course would like to get this issue resolved as soon as possible.
Finally and related, is there any tool with which one can view the contents of the `cyrus.*` files in plain text, particularly `cyrus.index`? I consider it might be helpful to see what's happening with the flags and very existence of a message file within the index in order to perhaps further diagnose the problem.
