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Thunderbird 153.0.1 new folders cannot be used

Thunderbird Email and messaging
ultrafox1 replied
ultrafox1
ultrafox1

I have used Thunderbird with the same email account for years, creating subfolders and moving emails to the subfolders with no issues.

With Thunderbird 153.0.1, after creating a new subfolder in the account, when attempting to move emails to the new folder, I receive the following error:

"Thunderbird: The current command did not succeed. The email server responded: APPEND invalid flag list"

I have used Thunderbird with the same email account for years, creating subfolders and moving emails to the subfolders with no issues. With Thunderbird 153.0.1, after creating a new subfolder in the account, when attempting to move emails to the new folder, I receive the following error: "Thunderbird: The current command did not succeed. The email server responded: APPEND invalid flag list"

All Replies (1)

ultrafox1
ultrafox1 Vlasnik pitanja

Here is some information supplied by the email account provider:

When creating a new folder, the server shows error: "{imaps} Bad flag in APPEND command: Nonjunk"

The error is clear — the IMAP server is rejecting the APPEND command because Thunderbird is sending two junk-related flags simultaneously:

$notjunk — a valid IMAP keyword flag NonJunk — a non-standard flag (no backslash prefix) that the server doesn't accept

This is a Thunderbird-side behavior — it's sending both $notjunk and NonJunk together when moving messages to newly created folders, and the server's IMAP parser rejects NonJunk as invalid.

Postavite pitanje

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