TEMPFAIL — TEMPFAIL

The IMAP server signaled a temporary failure (e.g., it couldn't process a request right now). This is usually transient. Your application should catch this and retry the operation after a delay. Riposte might automatically retry some transient errors, but you can implement a backoff strategy if needed. For example, if a fetch fails with TEMPFAIL, wait a bit and try again or let the next sync cycle pick it up.