[IMAP] unable to create folder "***@gmail.com/sent" on the server.

The following error message is appearing intermittently:

[IMAP] unable to create folder “***@gmail.com/sent” on the server.
([ALREADY EXISTS| Duplicate folder name (Failure))

I had this problem before and deleted and re-added my gmail account, which seemed to have fixed things, but now the error message has appeared again.

I’m using version 7.0.26567.0 and my OS is Windows 10.