How, or should I say what would be the typical methods used to control when a trial software program runs out? I have a device driver, that is supposed to stop functioning after Monday, next week. The driver is in the Windows/ System32/Drivers folder, and there is an entry in the registry under HKLM/System/ Current Control Set/ Services/ XXXXX.
Where does it read the time from, the actual BIOS, or system clock?
I am questioning, because I have this installed on a computer at my house, and the system clock is currently set at Wednesday, and everything is still working.

It's strange, but changing the Windows time will change the CMOS time too (I think this is a mistake though, basically gives access to CMOS settings from Windows)

Sometimes through Registry, sometimes through a file

Never heard of drivers expiring, why don't you partition your drive and install the driver there and keep formatting it everytime yuor trial software almost expires.

I was told trial would stop working Monday. I have computer bios and system time (yes setting system time did change bios clock) up to Thursday and everything is still working, and I am wondering if I was told it expires, but it doesn't. It hasn't, so far.

hum; not thrilled on the ethics of this

If you need it, pay the fee else uninstall it. Life can be simple if you let be

reverse enginering or freeze clock more legal

reverse engineering is not legal in many areas. Basically you are stealing intellectual property.
I think it is time for this thread to be closed.