Usbser.sys BSOD with Pololu Connected

I was able to determine that this servo was the issue connected to the continuous crashing of my windows 7 64 bit computer. This diagnostic was performed by going to the device manager, viewing devices by connection, and disabling the usb composite device that contained the 3 pololu devices, which has stopped the crashing.

Pololu Mini Maestro 24-Channel USB Servo Controller has driver version
Pololu Mini Maestro 24-Channel USB Servo Controller Command Port (COM4) has driver version
Pololu Mini Maestro 24-Channel USB Servo Controller TTL Port (COM3) has driver version

I have tried reinstalling, which did not solve my problem. The odd thing is that this has been stable for a couple years, and this issue has only just come up in the past few weeks.

I am controlling the servo through Labview 2013 (64-bit) NI-VISA serial connection.

The specific error I am getting is:


usbser.sys - address FFFFF8805FFA161 base at FFFFF88005F1000

I know this is probably an insufficient amount of information to diagnose the issue, so please let me know what else I can provide to help figure this out. Thanks!


I moved your post to our Servo controllers and servos, which seemed more appropriate.

Were there any updates to your system between when it was working and now? What version of usbser.sys do you have running on your computer? You can find what version you have by looking in the “Details” tab of the “Properties” window for C:\Windows\System32\drivers\usbser.sys.

- Amanda

Hi Amanda,

Thanks for the prompt reply. I have windows update turned off and did not check for updates in between it working and not. I have tried using system restore to revert back to a previous time, but the problem has persisted.

The usbser.sys version I have is 6.1.7601.18247

We tried to reproduce the problem on our Windows 7 machine running the same usbser.sys version (6.1.7601.18247) here, but are unable to. Are you running the Maestro Control Center or any other software using the Maestro at the same time with your LabVIEW program? What Maestro commands are you using in your program and how often are you sending them to the Maestro? Is there a USB hub between your computer and the Maestro?

By the way, I did a quick search to see if others have encountered a similar problem when using USB devices in LabVIEW and found this thread on National Instruments forum. The last post on page 3 by rolfk might be what’s causing the issue. You might try the VISA synchronous mode workaround and see if that fixes the problem.

- Amanda

Hi Amanda,

Thanks for pointing me to the NI forum. It discussion there sounds very similar to my issue, and I have switched the communication to synchronous mode. There haven’t been any issues so far, so the workaround seems to have solved my problem. It is hard to tell because the BSOD is random, but it’s looking good so far.

Thanks again for thoughtful and prompt responses!