your patch didnt work for me, but im sure its my "one size fits all plc lappy" (dos,win98,xp sp3)configuration.
not your hard work.
it couldnt find c:\windows\driverscache\i386\sp3.cab.
i extracted what i think is the sp2 version of serenum.sys (date 08/03/04) out of driver.cab in my version of the above (e:\xp\driverscache\i386).
i changed the attributes to the sp2(?) file from archive to system/read only (i removed the archive attribute).
i then over wrote e:xp\system32\drivers\the offending serenum.sys dated in 2008.
i rebooted.
system32\drivers file remained the same (2004).
i re-read the rest of this post and searched all versions and replaced with the 2004 version.
i think changing the older file attributes from archive to system\read only, kept xp (or most versions of windows) from doing the things that **** most of us off.
i will test at work tonight.
for the curious of my one size fits all 333celeron gateway with pcmcia and floppy and serial and usb.....
c:\drive fat16 2gb dos, d:\drive fat16 2 gb, e:\drive fat32 win98 15gb, (win98 changes to f:\drive while in xp),e:\drive ntfs xp sp3 17gb.
no operating systems are in a directory called windows.
anything loaded in win98 cannot crosslink to xp due to ntfs.
so far nothing has crosslinked from xp to win98.
if i ever find a need to have to use windows 3.11, d:\drive is ready.
if xp ever tells me i cant access it, a program called ntfs4dos is on my win98 partition.
thanks dmroeder for pointing me in the right direction for the exasperating reason for xp mode being hit or miss.