I have taken that precaution. Thanks.

I've been getting problems with this folder, sorted until now by reindexing.  This time even that is blocked by a message reporting a corrupted master file.  I tried to post in this forum and couldn't. Now I'm reporting that I shut down pmail and restarted it and it's now OK.  Any comments?

Your first post did come through,  In fact, I was about to hit send on a reply when this one showed up.  I'm glad the restart solved the problem.  I can't explain why the problem occurred but a restart is always a good first troubleshooting step.

One thought: Be sure you have your mailbox directory excluded from active AV scanning.