TAZ5 no longer communicates USB

I have a TAZ5. Running latest edition of CuraLulzbot. After a big Windows update install, the desktop can no longer print via USB to the printer. When I use the same software version on a laptop, with the same USB cable, it communicates with no issues / prints fine.

Can someone please tell me what Windows “switch” to flip back, so CuraLulzbot can communicate with the printer again through the desktop?

Had the same problem with USB communications to an piece of test equipment after a windows 10 update. I ended up opening Device Manager and locating the USB entry for that device. Deleted the driver and reinstalled. Note that just trying to do an “update” did not work. Windows reported I had the latest update. I found out that the only way to update it was to delete and get the update from “windows update”. After reinstalling the drivers it worked again. If I can locate the post I made to the forum for the electronic equipment in question, I can post what I did. The names of the drivers will be different but the steps should be about the same.

Let me try this again. Below is a copy of what I did to fix a similar issue for a piece of test equipment called a Nano VNA. Note that the driver name may be different for TAZ but the process should be about the same. I suspect the reference to the knowledge base “KB” article probably does not apply. By now other updates would have replaced this one.

Again, this was for a different device so the names will be different. It may not be “Cypress” in this case.

"After the latest Windows 10 update the COM port was either not showing up or it was there but the software could not see it. The NANOVNA did not recognize it was there.

Running USBview SDK debugger tool I found under Universal Serial Bus Controllers (Device Manager) that the PC sees the NANO as a “USB to UART Adapter”. Cypress driver. You don’t need to install this SDK tool now that you know what USB controller the NANOVNA will use.

Before going any farther check for updates. See that KB5000842 is installed. It installs as an “optional” update. The description is “2021-03 Cumulative Update Preview for Windows 10 Version 20H2 for x64 based Systems”. If that does not fix the issue then proceed as follows:

In Device Manager, locate the USB to UART Adapter. Right click and select “update driver”. Select “Search automatically for drivers”. If it returns and indicates the current drivers are already installed then uninstall the USB to UART Adapter device. If a COM port was assigned (in Device Manager) uninstall it also. It will be the one with the Cypress driver. Note, that the NANO should be disconnected from the PC. Reboot the PC. Now, plug in the NANOVNA.

On the laptop reinstalling did the trick. On the Windows 10 desktop the steps above did not work. I tried to update the drivers again but selected to look for a new driver via Windows Update. It found a Cypress driver. Installed it, rebooted PC. Now in Device Manager I see “Other Devices” that contains “Virtual Serial Port Device 00” It has a yellow triangle in the icon indicating a problem. Right click and select update driver, Search Automatically for drivers. It failed but suggested I try via Windows Update. View optional updates and expand the list. Still showed Cypress which I installed again. Now the “Other Devices " disappeared. COM port 5 showed up. THAT WORKED! Starting NanoSaver software it now sees COM5 and the VNA. If the software is already running when installing the driver, shut it down and restart. Best to restart the PC too.”