Troubles using two USB-4065

[Wolfgang Weber]

I try to use two USB-4065 at a PC driven by Windows XP. Driver version is NIDMM3.01.

I can use one USB-4065 or the other one. If the first one works and I connect the second one, the second will not work. If I disconnect the second one again, the first one stops working, too. In one of six or seven attempts both of them work. The Problem can be observed during usage of LabView as well as usage of soft panel. Change USB ports does not help.

Is there any solution for this Problem?

[Matteo_Bax]

USB Data Acquisition Device Not Responding (bezieht sich auch auf den Fehlercode "-1074118650", da das Gerät ja teilweise nicht erkannt wird)
http://digital.ni.com/public.nsf/allkb/3EA2432762C45B298625734D0061D527

Internal Hardware Error -1074118650 (BFFA4006) with an NI 407x DMM
http://digital.ni.com/public.nsf/allkb/3688C9E7FEF93E45862576E6007ED955

USB-4065 SFP driver version 2.9 not work in Vista Premium
http://forums.ni.com/t5/LabWindows-CVI/USB-4065-SFP-driver-version-2-9-not-work-in-Vista-Premium/m-p...

DMM PXI-4070 Internal Hardware Error - 1074117756.000000
http://forums.ni.com/t5/Digital-Multimeters-DMMs-and/DMM-PXI-4070-Internal-Hardware-Error-1074117756...

[Steve_B]

Hi Wolfgang,

What type of computer are you using? Is it a laptop or a desktop? Do you receive an error from the driver when one of the devices is not working or does Windows not recognize a device? There could be an issue with the amount of power the USB ports are supplying and if it can handle having 2 USB DMMs connected. Is there anything else connected via USB? Can you try removing the additional devices to see if that helps? Do you have another computer to try connecting the DMMs to? I would be interested to see a screenshot of your Device Manager when one of the devices is not working. 

[Steve_B]

Hi Wolfgang,

I wanted to see if you were still running into that issue connecting two USB-4065's to your computer. The first link from teobax addresses some known issues that can arise with multiple USB devices connected to a single computer. Were any of these troubleshooting steps helpful?