I have a gmail account accessed as imap.  It does the same thing.  I presume the problem is on the google side as I've never had problems with the imap protocol before.  As you say, the actions in fact are reflected in the account regardless of the the warnings.  I don't believe it is the xfinity/comcast modem as the last time I used imap it was with another source and there were no problems.

Be well,

Kim

Throughout the day, almost every operation that I attempt (e.g., SEND, DELETE, etc.) is greeted with the message: 

"The

IMAP Server that manages your mailbox or folder reports an error during

the operation you have attempted to perform.   The operation cannot be

completed."

 This message occurs (accompanied by a bell)

sporadically, even when I'm not doing anything.  What's curious is that

the messages that I send *are* getting to their destination but are not

being save in the folder where they belong.I downloaded the latest

version of PMail, but it has had no effect.

Yesterday, I installed a new Modem from Xfinity.  Could that be the cause of these problems?

 RonM