Microsoft released an emergency fix for its latest Patch Tuesday update that prevented some users from creating new virtual machines on certain Hyper-V hosts.
The problem that affected users of Windows Server 2019 and Windows Server 2022 was due to KB5021249 (opens in a new tab) or KB5021237 (opens in a new tab) updates installed on Windows Server or Azure Stack HCI hosts.
Existing VMs are not affected by a buggy update according to status update (opens in a new tab) from Microsoft, only new virtual machines created after installation.
What now for users?
Microsoft has resolved the out-of-band (OOB) updates released on December 20 for installation on Hyper-V hosts in your environment.
Microsoft says that you do not need to install any updates or make any changes to other servers or client devices in your environment to resolve this issue.
If you want a standalone package for these out of band (OOB) updates, you can search for the KB number in the Microsoft Update Catalog (opens in a new tab).
Microsoft says you can then manually import these updates into Windows Server Update Services (WSUS) and Microsoft Endpoint Configuration Manager.
This is not the first time in 2022 that the Patch Tuesday update has caused serious problems for users.
In December 2022, an update called KB5019980 caused database connections that used the Microsoft ODBC SQL Server driver to fail.
However, the tradition of weekly Patch Tuesday updates may not last forever.
In July 2022, Microsoft introduced a tool that will use Windows Update for Business to automatically deploy important updates.
Dubbed Microsoft Autopatch, the tool for Windows 10 and 11, Microsoft Edge, and Microsoft 365 is now available to users with Windows Enterprise E3 and E5 licenses.