Microsoft confirms Windows Server Update Services sync delays

Summary

Microsoft has acknowledged a widespread issue causing synchronization delays and timeouts for Windows Server Update Services (WSUS). This problem, observed since mid-July 2026, prevents IT administrators from deploying the latest Windows updates to enterprise networks. While mitigation measures have been applied to new WSUS installations, Microsoft is still working on solutions for previously affected servers.

Full text

Microsoft confirms Windows Server Update Services sync delays By Sergiu Gatlan July 20, 2026 06:47 AM 0 Microsoft is working to fix a known issue affecting Windows Server Update Services (WSUS) servers, which has caused synchronization problems for more than a week. WSUS was introduced almost twenty years ago to help IT administrators schedule updates for Microsoft products on enterprise networks from a single local update server, rather than updating each endpoint directly from Redmond's servers. By default, WSUS syncs with Microsoft Update servers once a day to download the latest metadata for available Windows updates. However, on servers affected by this issue, synchronization is broken, and admins will not be able to deploy the latest Windows updates via WSUS or Configuration Manager. According to Microsoft, the WSUS sync issues affect both client (Windows 10, version 1607 and later) and server (Windows Server 2012 and later) platforms. "Organizations might experience increased synchronization times or sync operation timeouts on WSUS servers. This issue began in recent days, with heightened impact observed starting July 13, 2026," Microsoft said in a Windows health dashboard update. Microsoft has rolled out mitigation measures on Saturday to prevent WSUS sync times and operation issues from affecting newly installed or rebuilt WSUS servers. However, it is still working on additional mitigations for previously affected WSUS servers that continue to experience WSUS synchronization issues. "Synchronization times and sync operations on WSUS servers have been restored and are operating normally for new WSUS installations and rebuilds," it added. "For WSUS servers that were previously affected, Microsoft is working on mitigation steps to help customers safely remove the affected metadata from their environments." One year ago, in May, Microsoft fixed another similar issue after enterprise customers reported being plagued by WSUS errors when trying to update Windows 11 22H2/23H2 systems. Microsoft addressed another WSUS issue in July 2025 that prevented organizations from syncing with Microsoft Update to deploy the latest Windows updates. One month later, Microsoft resolved one more issue that blocked the August 2025 security update from being delivered via Windows Server Update Services (WSUS). Test every layer before attackers do Security teams log 54% of successful attacks and alert on just 14%. The rest move through your environment unseen.The Picus whitepaper shows how breach and attack simulation tests your SIEM and EDR rules so threats stop slipping by detection. Get the whitepaper Related Articles: Microsoft fixes Windows update failures linked to WUSA installerMicrosoft: Some Windows PCs fail to install latest monthly updatesMicrosoft fixes KB5089549 Windows security update install issuesWindows KB5121767 OOB update fixes shutdowns on some Dell PCsMicrosoft: Some Dell PCs shut down after recent Windows updates

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