Apparently he never read how the UPGRADE worked. But them many ppl DO NOT READ , several methods to remedy the problem were offered. the easiest is Install the Genuine DL edition w/o a key.... DUH he then has 30 days to Activate. then chose install again, it will ask if he wanted to UPGRADE, this is the method M$ recommends for the UPGRADE EDITION, the answer would be YES then enter the UPGRADE KEY.... DUH, then he would have a 100% Genuine Install and not have to worry about DAZ loader being found an WOOPS now he is "NOT GENUINE"......... jesssssssssssssssssssssse has a legal KEY and is using a HACK.
Further testing is showing Setup's test for a "previous version" is very lazy. It is sufficient for there to be a "Windows" folder on the drive. It can be empty. I know Windows98 checked for winver.exe and win.com.