Tracking not working correctly on my lasers after Windows KB5066791 update

Today (6 Nov 2025) my Windows 10 laptop applied a Windows Update (KB5066791). After this, Lightburn is having tracking issues with both my Sculpfun iCube 3w and my Comgrow Z1 5w lasers.

I’m still able to communicate with them and even get the lasers to respond to commands. However, they both get an alarm and try to run off their track when I try to frame a job.

In the console for the Z1 it reads: ALARM: 1 Hard limit triggered. Machine position is likely lost due to sudden and immediate halt. Re-homing is highly recommended On or near line 1:

In the console for the iCube 3w, it reads: ALARM: 3 Reset while in motion. Grbl cannot guarantee position. Lost steps are likely. Re-homing is highly recommended. On or near line 1:

I am running Lightburn Pro 2.0.04.

The Z1 console shows VER: 2.3.0.2.20230830:#I
OPT: VZL, 15, 128

The iCube console shows: VER:1, 1h.2023110301:
OPT:V,15,1281

I’m guessing this is not going to be a version issue for either laser, since they worked fine yesterday. Since both have this same problem, I’m guessing it’s a Windows communication problem after the update.

Obviously a Windows issue. Look up rerunning the C++ Runtime updater downloaded from Microsoft.

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If the updater doesn’t work as @MikeyH recommended, I’ve linked to the downloads for the two most common culprits below.
https://aka.ms/vs/17/release/vc_redist.x64.exe
https://aka.ms/vs/17/release/vc_redist.x86.exe

You may also need to restart your PC after installation.

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Did you try rolling back the update? You can always install the update again it might be worth rolling back just to see if that’s the issue.

Good evening soniclab. I did make the attempt at this, but the update refuses to uninstall. I knew that once the Windows 10 support was gone I was on borrowed time. I had not expected that they would push something to it after the cutoff date. I just figured I was going to have to worry about security issues, not Microsoft bricking the laptop. Thanks for taking the time to make the suggestion!

Good evening Joed. I ran this as well, but it did nothing for the issue. Thanks for your thoughts, though!

Good evening. Thanks for the thought. Unfortunately, rerunning this didn’t fix the issue.

UPDATE: I attached another laptop to the Z1 Comgro laser and it still works fine. So I think I may just be out of luck with the original one. Since it can’t be upgraded to Windows 11, I am thinking it’s likely not worth the time to build it back up from a factory reset. Thank you for all of your help!

I just scrapped an i3 Dell machine myself. Don’t forget to remove it from your list of licensed machines.

Thanks Mikey - I probably would have too.

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