GPIB communication issues between PC and device

Hi ,

I have a device, which has an older GPIB version(it is DOS95 base I think). And I want to hook it up to a WINDOWSXP PC which has an updated version of GPIB, but whenever I do it, the WINDOWS XP can't detect the device.

The device, can run on an old DOS based computer. I tried connecting to the device in parallel (using the windows XP PC), so I could check what GPIB commands trhe device is throwing(using NI SPY). But whenever I do that the device wont communicate. However, when I remove the parallel connection to the Windows XP, the device can communicate again.

Can you help me on this?

Thanks!
Appreciate your help