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IMAP

NOMODSEQ — NOMODSEQ

Mod-sequence not supported for mailbox

Riposte solution

NOMODSEQ means the server does not support tracking modifications for this mailbox. As a result, you cannot use mod-sequence based sync (QRESYNC) on it. Riposte will detect this and avoid modseq-dependent operations. It might have to revert to full sync checks for changes. No direct fix—it's a server limitation; just be aware that incremental sync might be less efficient for this mailbox.

Quick facts

Provider
IMAP
Endpoint / surface
IMAP Protocol

Why it happens

[Protocol-level condition per RFC/extension]

How to fix it

[Adjust client behavior per RFC semantics; often retry or change command/parameters]