The mail server for account DRM iCloud responded: [NONEXISTENT] Mailbox does not exist. (Thunderbird v78.5.1, 64-bit)
I have TB v 78.5.1 (64-bit) connected to nine email servers, including iCloud.
Every time I start TB, when it connects to each email server, a notification message comes back from iCloud, reporting:
Thunderbird The current operation on 'Inbox' did not succeed. The mail server for account DRM iCloud responded: [NONEXISTENT] Mailbox does not exist.
This is strange, because of course, both the iCloud account and the Thunderbird account really do have a mailbox called 'Inbox', along with every other email account I have ever used, and the contents of that Inbox are correctly synchronised.
This is little more than a daily irritation to me, but I wondered if anyone had any useful comment to make about it. If I could learn how to prevent the spurious notification appearing, so much the better.
Regards, David'
All Replies (1)
https://support.mozilla.org/en-US/questions/1026598 (generate a specific "mail key" in apple site, & use that code in TB as iCloud mail-account's password).
and, make sure you've entered spelling / each letters/numbers accurately: your full email-address in "User Name" field , server address, port number , auth-method, security, etc.