Using einstaller.exe to reinstall

If I reinstall a pc or just NOD32 (using an automated deployment system) the installation of NOD32 version 3.0 using einstaller.exe fails when the pc had NOD32 installed before the reinstall.

In my installation package I make sure that "HKLM\SOFTWARE\Eset\ESET Remote Installer" is deleted but I have to go to the server and clean out the previos record of a successfull og failed installation before the reinstallation will work.

Isn't there a way to force a reinstall (like a parameter on einstaller.exe) without the manual process of going into the console and doing a Clean?

Do I have to install the client without using einstaller.exe instead?

Best regards
Preben