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Windows Update KB5009543, KB5009566 breaks L2TP VPN connections (Update)

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Microsoft released Windows emergency out-of-band (OOB) updates to fix multiple issues caused by January 2021 Patch Tuesday updates.

Update from https://www.swfit.io/news/windows-update-kb5009543-kb5009566-breaks-l2tp-vpn-connections/

Microsoft has released emergency out-of-band (OOB) updates for Windows to address multiple issues caused by security updates issued as part of the January 2021 Patch Tuesday.

The Windows Server updates for January were causing a series of issues for administrators, multiple administrators reported anomalous reboots of Windows domain controllers, and Hyper-V that was no longer starting on Windows servers.

Reports also claim that the Windows Resilient File System (ReFS) volumes were no longer accessible after the installation of January 2021 updates.

Some administrators and users reported problems with L2TP VPN connections on Windows 10 after installing the recent Windows 10 and Windows 11 cumulative updates.

“Microsoft is releasing out-of-band (OOB) updates for some versions of Windows today, January 18, 2022,” the company said. “This update fixes issues related to VPN connectivity, Windows Server domain controller restarts, virtual machine startup failures, and ReFS-formatted removable media that fails to mount.”

The OOB updates can be downloaded from the Microsoft Update Catalog, if they are not installed directly from Windows Update as optional updates.

Emergency out-of-band (OOB) updates through Windows Update are optional updates and have to be manually installed.

Below are the updates can only be downloaded through the Microsoft Update Catalog:

These are the updates for these Windows versions that are also available through Windows Update as an optional update:

  • Windows 11, version 21H1 (original release): KB5010795
  • Windows Server 2022: KB5010796
  • Windows 10, version 21H2: KB5010793
  • Windows 10, version 21H1: KB5010793
  • Windows 10, version 20H2, Windows Server, version 20H2: KB5010793
  • Windows 10, version 20H1, Windows Server, version 20H1: KB5010793
  • Windows 10, version 1909, Windows Server, version 1909: KB5010792
  • Windows 10, version 1607, Windows Server 2016: KB5010790
  • Windows 10, version 1507: KB5010789
  • Windows 7 SP1: KB5010798
  • Windows Server 2008 SP2: KB5010799

Users that cannot immediately install these out-of-band updates can remove the following updates that could cause the above problems:

  • KB5009624 
  • KB5009557
  • KB5009555
  • KB5009566
  • KB5009543

However, experts warn that removing the above updates they will also remove bundled security updates that address vulnerabilities patched with the release of the January 2021 Patch Tuesday. 

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Nicholas Salem

As the CEO of SWFIT, a leading managed IT services company, Nick Salem is responsible for providing strategic leadership and direction to the organization. With over 20 years of experience in the IT industry, Nick has a strong track record of driving business growth and improving operational efficiency through the use of technology.

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