XP version SFC /SCANNOW

My OEM PC has XP Home/SP2 pre-loaded.
Have the "Product Recovery" manufacturer's CD incl XP and drivers, which
"recovers", but cannot do a "clean" install.

I've posted earlier (problem with CHM files) but further reading prompted me
to run CMD = SFC /SCANNOW.

SCANNOW prompts me to insert the CD for XP PRO/SP2 - which I don't have.

This PC has never had any OS other than the originally loaded and genuine XP
Home. I did a "recovery" a while back (subsequently downloaded/installed 77
updates, so now allegedly completely up-to-date, with Auto-update on). Both
internal and external virus checks confirm no intections or malware.

Following the SCANNOW prompt for CD, inserted the recovery XPhome/SP2 disk,
no good, "wrong CD".

HELP!! Where's the need for "XP Pro" come from? How to correct?


.