Fix Gmail-Outlook Sync Issue

I run five different mailboxes inside Outlook Classic on Windows, and only the Gmail-based business address has suddenly stopped sending or receiving. Outlook shows no visible error code—it simply does nothing. I have already removed and re-added the profile, so the usual reset steps are done.

Microsoft support admitted there is a known handshake problem between Outlook and Gmail; apparently there is a specific fix involving the OAuth / IMAP settings that I don’t have in hand. If you’ve dealt with this exact Gmail-to-Outlook connection failure before and can get the account fully syncing again—without disturbing my other four accounts—let’s do it.

Success is straightforward: after your intervention I must be able to press Send/Receive and watch new mail arrive and outgoing mail leave from that Gmail address just as the others do. Remote access via TeamViewer or similar is fine, and I’m ready to test live once you say it’s fixed.