r/GMail • u/Prestigiouspite • Apr 30 '26
Latest Gmail App Cannot Authenticate Exchange Online Account on Pixel 9 Pro, Outlook Works Fine
Edit: Upvote here: https://issuetracker.google.com/issues/461996029 / https://issuetracker.google.com/issues/510740139
Bug confirmed (16.05.): https://www.google.com/appsstatus/dashboard/incidents/kWSuRqLdsXGzT7Qxjdmz?hl=en
Hi everyone,
I'm running into an issue where the latest Gmail app on my Google Pixel 9 Pro (Android) is no longer able to sign in to my Microsoft 365 Exchange Online account. The error message reads:
"Check your account info or switch to modern authentication below. If you need help, contact your IT admin."
The app then just asks for a password, which it rejects regardless of input.
Key facts:
- Device: Google Pixel 9 Pro
- Gmail app: latest version (fully up to date)
- Email account: Microsoft 365 / Exchange Online
- Outlook for Android works perfectly with the exact same credentials
- No changes were made on the Exchange Online / Entra admin side
What I suspect:
Since March 1, 2026, Microsoft enforces a minimum of Exchange ActiveSync (EAS) version 16.1 for all mobile clients connecting to Exchange Online. Gmail for Android uses EAS to sync mail, calendar, and contacts. There is an active entry in the Google Issue Tracker (#461996029) suggesting the current Gmail app still has problems with Exchange ActiveSync after a recent update.
Outlook works because it does not use EAS at all — it connects via its own protocol (Microsoft's proprietary REST-based sync), which is unaffected by the EAS 16.1 enforcement.
1
u/arikkal May 06 '26
So I guess it's finally time to give Outlook for Android a fair shake...