Windows Server KB5062557 causes cluster, VM issues

Microsoft is asking businesses to reach out for support to mitigate a known issue causing Cluster service and VM restart issues after installing this month’s Windows Server 2019 security updates.

As the company explains in a private advisory seen by BleepingComputer, the Cluster service (a system component essential to cluster operation) might fail to function correctly after installing the KB5062557 update released on July 8th.

The same bug is also causing some nodes to fail when attempting to rejoin their cluster and triggering errors on systems where administrators have enabled the BitLocker Windows security feature on Cluster Shared Volumes (CSV) drives.

“After installing the July Windows security update (the Originating KBs listed above), the Cluster Service on Windows Server 2019 might repeatedly stop and restart, causing nodes to fail to rejoin the cluster or enter quarantine states, virtual machines to experience multiple restarts, and frequent Event ID 7031 errors within event logs,” Redmond explained.

While a mitigation is available for organizations affected by this known issue, Microsoft has yet to roll it out to customers. Until the fix is generally available, the company asks those impacted to reach out to business support for help addressing these problems.

“If you need help to manage this issue on your organization and apply a mitigation, please contact Microsoft’s Support for business,” Microsoft said.

“ We are working to include the resolution in a future Windows update. Once the update with the resolution is released, organizations will not need to install and configure the mitigation provided from Microsoft’s Support for business.”

Earlier this month, Redmond addressed a widespread issue affecting Windows Server Update Services (WSUS) that prevented organizations from deploying the latest Windows updates due to Microsoft Update sync problems.

The July 2024 cumulative updates have also resolved an issue triggered by the June 2025 security updates, which caused the DHCP service to freeze on some Windows Server systems.