The computer names are stored in the licence file unless this is disabled by the No Client Licensing module. Computers that are no longer current or are not required can be enabled and disabled through the licence overview at any time.
If you own just one licence and the computer name has been changed, Password Safe will start in demo mode. You can open the licence overview from the Activation wizard or login screen by pressing the shortcut CTRL+F9.
Open up the structure in the licence overview by clicking on the small dark arrows in front of the folder icons. All the computers saved are listed under the Licence Numbers per Computer folder. You can enable or disable a computer by right-clicking on the computer name. This will then free up licences again so that new computers can register themselves in the licence.