Tips how to install Avira Free in Windows Server 2008 :

1.) Start –> Run –> Regedit
2.) Go to HKEY_LOCAL_MACHINE –> SYSTEM –> CurrentControlset –> Control
3.) Now change the permissions of the folder “ProductOptions” –> add your user account (for example Computername\Username) and deny yourself the read rights for the whole folder. Be careful not to deny the whole rights for all administrators or something like that (I tried that first cause of a black out and it leads to windows not being able to boot).
4.) Now you should be able to install Antivir PE

In case you want to revert the permission settings just log to your administrator account. Here you can again grant your user account full rights for “ProductOptions”.