Prestaged PCs cannot be reinstalled by RIS/WDS

We have several prestaged PCs that came with preinstalled OS (Windows XP) from the vendor. We cannot reinstall those PC neither via RIS nor WDS.

When I try to reinstall such as PC via RIS/WDS, I cannot use Automatic install because it fails to find the computer object in Active Directory based on its GUID (and install PC under default computername). When I try to use Custom install and I write PC name (which exists in AD), it reports Access Denied. The only possibility is to delete computer object from Active Directory and then to reinstall.

If the PC is initially installed from RIS/WDS, the reinstallation work without problems via Automatic installation. The PC is correctly recognized based on its GUID.

The object in Active Directory has no caption "Remote Install".

How can we make the Automatic installation running? How to to add caption Remote Install to the computer object in AD?

Thanks in advance for any help.