IMAP account not syncing in Windows 11 mail

Account is added manually with no problem - no error messages. However, the account does not sync. Inbox is empty. If I click the sync icon, it appears to be syncing, but after a few seconds it stops with no error message.

I have checked and double checked the mailbox settings (IMAP, SMTP etc.). The same settings work in Windows 10 no problem.
Tried reset, tried repair, deleted the account and started from scratch. Did this multiple times. Problem persists.

Emails from this account are received fine on my phone (Android 10) and laptop (Windows 10)

Outlook and Gmail accounts work fine in Windows 11.

Apologies if this has been asked and answered.

This
did not help either.

Is it a Gmail account?
Have you turned Less secure app access back on?

Edwin said:

Is it a Gmail account?
Have you turned Less secure app access back on?

View attachment 11935

Click to expand...

Thanks for your response.
It's not a Gmail account It is my ISP email address. Where can I find this setting?

I Googled it, and it seems to apply only to Gmail accounts. I am trying to set up the account in Microsoft Mail.

Works fine if I set it up in Gmail on the web, though.

What ISP are you using?

Try this (IMAP)

To ensure sync works properly go down each of the account names, right mouse click, choose IMAP folders and uncheck the "only show subscribed folders" --if you don't do that mail won't sync properly!

Cheers
jimbo