There appears to be a surge in reports from Windows 10 admins that this week's Patch Tuesday updates are causing problems with a range of enterprise printers.
Windows 10 admins report on Reddit that printer issues have arisen on Ricoh, Canon, Panasonic, and Brother printers after installing the June 9 Patch Tuesday updates KB4560960 for Windows 10 1903 to 1909 and KB4557957 for Windows 10 2004.
Some admins also note issues with Toshiba and HP printers after installing the update.
SEE: Windows 10: A cheat sheet (TechRepublic)
The reports emerged as Microsoft published a support note on Wednesday detailing an issue affecting Windows 10 1903 and later with USB-connected printers.
Microsoft said the USB printer port is missing after disconnecting or turning off a printer while Windows version 1903 and later are shut down. The vanished port pretty much means print jobs won't work anymore but, according to Microsoft, it only happens if the computer and printer are shut down in a specific order.
"If you connect a USB printer to Windows 10 version 1903 or later, then shut down Windows and disconnect or shut off the printer, when you start Windows again the USB printer port will not be available in the list of printer ports. Windows will not be able to complete any task that requires that port," Microsoft said.
Microsoft didn't specify whether a particular Windows update caused the problem, only that Windows 10 1903 and above are affected by the vanishing USB printer port issue. It also hasn't listed any printer-related bugs in the known issues section of each KB article.
However, release notes for the two KB updates state they contain "updates to improve security when using external devices (such as game controllers, printers, and web cameras) and input devices (such as a mouse, keyboard, or stylus)". The same updates were not mentioned in KB articles for versions of Windows 10 prior to 1903.
Some affected Windows 10 admins have reported solving the issue by either rolling back the Windows update or updating printer drivers. As noted by Windows patch expert Susan Bradley, the issue seems to affect Windows 10 devices with Printer Control Language (PCL) 5 drivers and PCL 6 type 3.
"All our users had Ricoh 4504ex PCL5 drivers which no longer work following update. Rolling back [the Windows update] or replacing with PCL6 driver resolves the issue," wrote Reddit user Shugwan.
"Backing out update KB4560960 and postponing updates seems to be our only salvation at this point. Hopefully Microsoft will produce a patch for this quickly, call volume is picking up with everybody returning to work, this is going to make things awfully hectic," reported another Reddit user, Groka-NT.
Rolling back Windows to an earlier build, of course, removes patches for 129 vulnerabilities included in the June 2020 Patch Tuesday update.
Fortunately, none of the vulnerabilities was exploited in the wild before Microsoft released the patches on Tuesday, though they did address around a dozen remote code execution vulnerabilities that could be exploited in future.
Some admins report that switching to PostScript drivers instead of PCL drivers fixed the problem, while others reported that uninstalling the security patches didn't resolve the problem.
It's hard to know whether the printer problem Microsoft disclosed in the support note is the same as the issues that users are now reporting after installing the Patch Tuesday updates.
But the timing of Microsoft's support note on USB-connected printer issues and the user reports on problems linked to Windows 10 versions 1903 and above suggest it could be the same issue.
Assuming it is the same issue, admins might have another solution, other than uninstalling the Patch Tuesday updates.
"You can avoid the issue by connecting a powered-on USB printer before starting Windows," Microsoft said in its support note.