To install APBackup in the unattended mode (no user’s actions required), you need to launch the installer with the following parameters:
apbackup.exe /VERYSILENT /SP-
After that, if you have an APBackup registration key, you can activate the program automatically. Just start the program with the following parameter:
c:\program files\apbackup\apbackup.exe QUIETREGISTER XXXXX-XXXXX-...-XXXXX
where XXXXX-XXXXX-…-XXXXX is your APBackup registration key.
The APBackup installation package was created using InnoSetup, so you can use any other supported command line parameters.