Your IMAP server wants to alert you to the following: Your IMAP client does not appear to correctly implement Unicode messages

Question

Our company email server is sending out this error message since I reinstalled a fresh copy of the latest version of Outlook:

"Your IMAP server wants to alert you to the following: Your IMAP client does not appear to correctly implement Unicode messages, see https://tools.ietf.org/html/rfc6855.html"

I did find a related setting and made adjustments, but the warning did not stop. Anyone knows what I need to do to fix this issue?

Answer 1

I have three Outlook/Exchange accounts, one IMAP and one Gmail account active in my Outlook. Only the unbranded IMAP account gives this message. It comes in looking like an email, but can't be found after closing. The message only started this week when I reset my PC and had to configure my PC from scratch.

I could remove the IMAP account and then add it manually to see if that makes a difference.

Answer 2

Apparently, it's because the client (Outlook) fails either to issue ENABLE UTF8=ACCEPT instruction before starting an Unicode transmission, or fails to mark UTF8 string literals as such, and it's not related to the settings OP made.

https://github.com/svarshavchik/courier-libs/issues/14

https://www.mail-archive.com/courier-imap@lists.sourceforge.net/msg04800.html