KB5004945 doesn't fix PrintNightmare for Zebra printer users

Microsoft has recently released an emergency patch in the form of KB5004945. This critical KB addresses a widespread issue regarding the Windows Print Spooler service also known as PrintNightmare.

This security threat, when exploited, it allows attackers to run arbitrary code with system privileges and then create new users with full access, view, or delete personal data. In other words, this vulnerability is a serious security problem for anyone using the WPS service.

You have to know that KB5004945 will show up as a direct update for Windows versions newer than v2004. Users with Windows 10 version 1909 will first get the KB5004946 patch and then the new emergency patch.

Also, as Microsoft stated in its official document:

The security update for Windows Server 2012, Windows Server 2016 and Windows 10, Version 1607 have been released. Please see the Security Updates table for the applicable update for your system. We recommend that you install these updates immediately. If you are unable to install these updates, see the FAQ and Workaround sections in this CVE for information on how to help protect your system from this vulnerability.

KB5004945 comes with huge bugs for Zebra users

While this new security update should solve the vulnerability on any Windows version newer than v2004, it seems that KB5004945 is causing lots of problems, especially for Zebra printers:

Is anyone having issues with older (maybe archaic) Zebra/Eltron 2844 printers and the new Windows 10 KB5004945 update? I’ve noticed the few stations we have with these older printers going through USB no longer prints. I uninstalled the update and it printed fine.

The same can be said about Lighthouse printers. While most of the affected printers are older models, some new ones seem to be affected, as well. One common resolution is to uninstall the update to fix any bugs caused by the emergency patch.

Another confirmed solution by many users is to re-install the printer’s driver without uninstalling the update, but the original driver has to be signed. We have to mention that reinstalling the driver only worked in some situations.

This massive issue was already confirmed by Zebra as being a direct consequence of KB5004945:

Email response from Zebra confirms that it is indeed this update breaking various printer models and instructing us to roll it back. Will keep updated with further responses as obviously “just keep this security update from ever being installed” is not the best solution

For now, there’s no official statement or resolution from Microsoft regarding the bugs that followed the emergency patch, but it’s safe to assume that another similar update will follow shortly.

Until then, if you’ve bumped into this problem, we’ve created a dedicated step-by-step guide with workarounds and fixes that will surely get your printer up and running in no time.

Dymo printers users are also affected

It would seem that not only Zebra printer owners have encountered problems after the installation of KB5004945. Apparently, the cumulative update brought the same issues to other brands as well.

People that use Dymo printers are starting to post all across social media that they are going through a similar struggle.

It still unclear how many types of printers are actually affected by this whole PrintNightmare situation, but we are sure that more will step forward and announce the strange behavior.

We are having issues with various USB Dymo printers after PrintNightmare patch installation.

Has anyone seen a workaround or solution to have them work with the PrintNightmare patch installed?

Don’t forget to tell us your experience with Microsoft’s latest KB in the comments section below and we’ll try to get back to you as soon as possible.