[netwolf]

Gary, have you done any firmware updates on the cameras?
Is it possible you have loaded a Qhy5 firmware update on the Qhy8 camera? Internaly they may share a usb chip and often this is programmed with VendorID and PID and a name, so when you plug in the camera it is identified as a particular named device. The OS then searches your drivers INF file to find a driver file that has the same vID and PID and loads that driver. Now if by some mistake your QHY8 thinks its a Qhy5 then it will load the Qhy5 drivers.
I know that Q cameras are rebadged and sold under diffrent names and you can get difffrent drivers depending on which firmware you load on it. Essentially all they do is reprogram the VID and PID to something else and change the name of the device from Say qhy5 to Qguider etc. This allows the one camera to use drivers written for different purposes and for diffrent rebadged brands.

If you had them both connected when you changed the firmware on them perhaps the wrong camera was updated and now your Qhy8 is being recognized as a Qhy5.

Let it install the Qhy5 drivers and update the firmware to a qhy8 firmware. Then uninstall and reinstall the Qhy8 drivers.

Tom might be your best bet to ask about how to fix this see his list of VID/PID's used by different resellers.

Regards
Fahim