Copy The file tbav-mcc.exe into the the c:\tbavw95 directory.
Then in the the Dos-Mode, go to the tbavw95 directory
Example: c:\>cd\tbavw95 Enter
         c:\tbavw95>

Then Type tbav-mcc RegName(yourname) then hit Enter

Then choose: for older version of ThunderByte: 
             Calculate key codes only

             for newer Version 7.0 and up:
             Calculate and create tbav.key

This Will Register ThunderByte Anti Virus