Reports have emerged from a variety of Android users experiencing authentication issues with the Gmail app when attempting to access their Microsoft 365 or Exchange Online accounts. This predicament has effectively barred many from accessing their work emails on mobile devices, despite the Outlook app functioning seamlessly with the same credentials.
Widespread User Impact
Over the past week, a growing number of users have taken to a Reddit thread on r/GMail to share their experiences. Participants hail from a diverse array of devices, including Pixel 7, 8, 9, 10, Samsung S24, Sony Xperia, OnePlus, Xiaomi, and Motorola. An IT consultant contributing to the discussion reported that over 500 end users across 50 companies are grappling with this issue.
The error message displayed by Gmail reads: “Check your account info or switch to modern authentication below. If you need help, contact your IT admin.” Users have noted that the app prompts for a password, but regardless of what is entered, it is consistently rejected. In a perplexing twist, attempts to delete and re-add the account have often exacerbated the situation, with some users unable to restore access to their accounts entirely.
Possible Causes and Technical Insights
The original poster in the Reddit thread speculates that the underlying issue may be linked to Microsoft’s enforcement of Exchange ActiveSync (EAS) protocols. A significant change was implemented on March 1, 2026, mandating EAS version 16.1, which blocks mobile clients operating below this version from connecting to Exchange Online. Since Gmail relies on EAS to sync emails, calendars, and contacts, it appears to be particularly vulnerable. In contrast, Outlook utilizes Microsoft’s proprietary REST-based sync protocol, allowing it to remain unaffected by these changes.
Additionally, discussions in the r/de_EDV subreddit have surfaced, with users in Germany also reporting similar challenges. An active entry on Google’s Issue Tracker highlights ongoing issues with the Gmail app and Exchange ActiveSync, dating back to November 2025, indicating that this is not an isolated incident.
Temporary Solutions and User Recommendations
While some users have attempted to resolve the issue by clearing the Gmail app cache, this solution has proven unreliable. A few have found temporary success by wiping all app data and storage for both Gmail and Android System WebView, only to face recurring credential prompts within hours. One user noted that their access lasted just a day before the issue resurfaced.
At present, the most stable workaround recommended by users is to switch to Outlook for Android. This solution, however, may not sit well with those who prefer Gmail for its integrated features. As of now, neither Google nor Microsoft has released a public statement addressing the ongoing authentication challenges.
