Disconnected USB devices remain in Measurement and Automation Explorer

[MDKF]

Hello. I frequently encounter VISA beleiving removed USB devices sill are still attached. Restarting the "NI Configuration Manager" does not help. This issues seems to occur most often on Windows 7 x64 machines. Any ideas on how to prevent this? Thanks.

[SunshineDesign]

What version of MAX arfe you using? I had a similar issue with an older MAX hooking to a USB device and falsely thinking it was a NI device and it was unremoveable. Even running the Corrupt database vi to purge the database for Max did not remove it. I had to upgrade to the most recent MAX version that came with NI-DAQmx 9.0x to resolve the issue. Try that and see if it help resolve the issue.

[MDKF]

Thanks for your reply. I have VISA 5.1.1 installed.

[JL@NI]

Hello MDKF,

What version of Measurement & Automation Explorer are you using?

Regards,

Jeff L.

[MDKF]

Hi Jeff,

5.0. The issues goes beyond measurement explorer however, software writen in c# using the VISA libraries also see the disconneceted board.

[JL@NI]

Hello MDKF,

How are you disposing of the reference to that resource in your code?

Regards,

Jeff L.

[MDKF]

Hi Jeff,

 We have not seen this issue on Windows XP. I have had devices stay stuck in VISA even if no software is accessing VISA other than Measurement and Automation explorer so I don't think it is related to how references are being disposed.

[alcava.cr]

Try with the MAX Database Corruption Removal Tool. If this does not work, go to the add/remove programs and repair the installation of VISA. By the way, what is this USB device that you are using?

[MDKF]

I have tried both of these already. The next time a device is inserted and removed, the problem recurs. I am using a custom USB device.

[alcava.cr]

Then let's attack this from the windows point of view. I've seen a couple USB issues going away by simply using a USB hub. Also, try removing and redetecting the device with the DevCon command-line utility (see this link fro more info), after this operation does the device behaves the same? Then, If you have something like the USB Safely Remove tool, it can help you and give you more information on what is keeping the device locked in the computer. Perhaps something related to the Distributed Link tracking service like mentioned in this other tread