A type of PC Access user authorization that resides on your computer's hard drive. You cannot uninstall a machine tie user authorization with the UAM, so installing it on your computer is irreversible. However, the machine tie user authorization resists damage from disk optimizers, disk compression programs, and backup/restore utilities. The UAM can back up your machine tie user authorization to your "PC Access for Windows - Disk 1." Your machine tie user authorization remains valid as long as you have not replaced your CPU, BIOS, or motherboard.