Security News > 2024 > February > Microsoft: Outlook clients not syncing over Exchange ActiveSync

Microsoft warned Outlook for Microsoft 365 users that clients might have issues connecting to email servers via Exchange ActiveSync after a January update.
"After updating to Version 2401 Build 17231.20182 Outlook stops connecting when using the Exchange ActiveSync protocol," Microsoft said.
Until this EAS syncing issue is resolved, Microsoft provides a temporary fix for affected users to revive their Outlook desktop clients.
In December, Microsoft addressed two other bugs, one behind email sending issues for users with lots of folders and one causing Outlook to crash when sending emails from Outlook.com accounts.
News URL
Related news
- Microsoft Exchange Online outage affects Outlook web users (source)
- Critical RCE bug in Microsoft Outlook now exploited in attacks (source)
- Windows 10 KB5051974 update force installs new Microsoft Outlook app (source)
- Microsoft's End of Support for Exchange 2016 and 2019: What IT Teams Must Do Now (source)
- Microsoft fixes Outlook drag-and-drop broken by Windows updates (source)
- Microsoft says button to restore classic Outlook is broken (source)
- Microsoft: Exchange Online bug mistakenly quarantines user emails (source)
- Microsoft fixes button that restores classic Outlook client (source)