I have recently found that when I save the attachments from a message and return to the relevant folder, then visit another folder, when I return to the folder in which the message was sitting, it has vanished. It took me a while to work out what was happening and to be able to reproduce the problem.

This is proving awkward where I need to reply to the message. I don't know of any setting that would cause this behaviour. Any suggestions as to what might be the cause?

I can not duplicate this in Pegasus Mail v4.81 public beta. Here are two things I would do to try to troubleshoot it.

1. Enable the "Preserve deleted messages until Pegasus Mail closes" option it it isn't. This way, if the messages are somehow being deleted, you will see them in the Deleted messages folder. Consider whether you also want to enable the "Deleted messages folder persists between sessions" option. Without it enabled, the Deleted messages folder get cleared on Pegasus Mail shutdown.

2. The next time you save an attachment, make note of the subject line of the message. If that message disappears, do a search of the entire mailbox for that subject line. Finding it in a different folder indicates that a filter is moving the message.

Thanks for the response. I already have "Preserve deleted messages until Pegasus Mail closes" option on. I did try searching the whole mailbox for the subject line and nothing found.

What I did realise is that the version of Pegasus that I was using was very old indeed. Version 4.72.572, Feb 19 2016, build 572. I have now updated to v4.81 public beta and not only has the problem gone away but the missing files have reappeared. I should have done this sooner. Thanks again for the input.

I am glad the upgrade fixed the problem, and that you chose 4.81 public beta. It fixed some problems that were in v4.80. I hope 4.81 comes off beta status soon. Some folks won't try it because it is a beta. That is a shame because it is a solid version.