Microsoft's fix for PrintNightmare causing some printers to not work

Zebra printers won't work following the installation of Microsoft's patch for the PrintNightmare vulnerability.

What you need to know

• Microsoft's patch for the PrintNightmare vulnerability is causing some printers to stop working.
• Zebra printers are among those affected by the update.
• Microsoft is aware of the issue and is working to address it within the next two business days.

A vulnerability known as PrintNightmare can be exploited to "install programs; view, change, or delete data; or create new accounts with full user rights," according to Microsoft. Due to the severity of the issue, Microsoft issued an out-of-band update for several versions of Windows, including Windows 10, Windows 8.1, and even Windows 7. In addition to people reportedly finding ways around the patch, the fix also stops some printers from working.

Following the installation of the KB5004945 patch, many printers won't work, including those from Zebra. A Reddit post highlights the issue, which has been confirmed by Zebra.

Microsoft shared a statement with The Verge regarding the issue:

We are aware of a printing issue caused by the July 6 Windows "KB5004945" update affecting multiple brands of printers. Microsoft has investigated this issue and plans to release an update addressing the issue within the next 1–2 business days. An immediate way to address the issue is to uninstall the Windows "KB5004945" update or uninstall the affected printer driver and reinstall using Administrative credentials. Long term, we encourage the use of the newer Windows update Microsoft is planning to release. Customers who need assistance regarding Zebra printers may contact our Technical Support Team.

The company also explained that an updated patch that should address the issue is on the way in the next couple of days.

The PrintNightmare saga continues to evolve. While people report ways around the patch for the vulnerability, Microsoft claims that the patch works as intended, and is only ineffective when people change default registry settings.