If you've ever manually updated your drivers, chances are you would have seen the driver incompatibility warnings that Windows generates telling you the driver you're installing isn't digitally signed or may be incompatible with your hardware. Here’s how to resolve each type of conflict.
Both Windows XP and Windows Vista have a Driver Protection List blacklist that stores records of drivers that are known to be incompatible or break things in Windows by default. If you attempt to install a new device or program using a Setup.exe file, Driver Protection will almost always pop up and alert you: '... driver is not compatible with this version of Windows.'
However, there is a workaround to force the installation through: loading the 'incompatible' driver by bypassing the Setup.exe, Windows XP will be unable to prevent the installation of the new driver. The downside is that it still may not load properly sometime in the future. If this is the case, Windows will alert you by popping up a balloon-warning in the Taskbar letting you know that the driver didn't load properly.
Of course, the first thing to try when troubleshooting is to disable or remove the driver that's incompatible. You may also have to remove an entire program if the driver was specially packaged with a software program. Adobe is particularly bad for this. Simply navigate to Add/Remove Programs to remove the offending application.
Note: Always create a system restore checkoint in Windows prior to making any significant system or program changes.