Device Instance ID changed from PID_F850 to PID_6001

[Guest]

It was working. Changed my tuner and along with it the drivers and now Windows XP will not recognize the 1.4 drivers. It thinks it is a "USB Serial Converter". The device instance id is PID_6001 and the .inf for the correct drivers says it should be PID_F850. If I modify the .inf it installs and recognizes it in the device manager as a USB-UIRT device but no applications that use it recognize its presence.

ideas?