First thing is remove any drivers that might have been already installed, you can only have one driver and tablet installed at one time. There are ways around it but that is very advanced. Best place for drivers is the tablet's manufacturer's website unless you have some Chinese made tablet that is a knock off of another brand or uses their parts then you can sometimes find better drivers but that is a rare instance.

Make and model info would help here. Wacom, for example, cannot co-exist with any other tablet on a system. You have uninstall all Wacom drivers and software, even if no Wacom tablet is currently connected. Other OEM's have similarly weird issues.

What issue or behavior are you observing?