Well, maybe I can help.
First, the date that you installed the software will be all over the
hard drive as the "date" on various folders (note: folders, not files),
in particular in the "Windows" directory, the "system" and "system32"
folders. To see the dates, if they are not shown, click on "view", then
"details" while looking at the folder from within "My Computer" or
"Windows Explorer".
Second, you may well be able to use the cd from your laptop. All cds of
the same type are the same, it's the product keys that are unique. So
if, for example, both your laptop and your desktop were upgraded using
[different] copies of the retail upgrade version of Windows XP Home,
then those CDs are identical anyway and, yes, you can use the laptop's
CD on the desktop computer [and it's even legal]. [Note, I'm only
talking about the CD, not the product key].
You still need the product key for the desktop, for that you can't use
the one from the laptop. If the desktop is still running, there are a
lot of programs that can extract and display the product key from the
installed running system. I like Aida, but there are about a dozen
others, a web search will turn them up.
A couple of suggestions:
If you are going to reformat your hard drive, find [web search] a
utility that will let you manually set the volume serial number, and
keep it the same before and after the reformat (essentially, reset it
after the format to the value it had before). This removes one item
from the Microsoft Product Activation checks.
Also, after you reformat and have a blank disk, if you are using FAT32
partitions, copy the I386 partition to the hard drive from the CD, then
do the installation from the I386 partition on the hard drive rather
than from the CD. Later, create a text file "Prodkey.txt" in that
folder that has the Windows XP product key for that computer. This
advice applies to NTFS as well, in principle, but it's very difficult to
do this with XP since you can't boot to a DOS disk and access an NTFS
partition.
I want to reformat my desktop HD. I can't find my XP Home Edition install
CD. I registered and activated the original installation with MS. I
contacted MS, they advise they can't help me unless I can find the software
box, or my receipt. There's a chance I can find the receipt, it would be
lot easier if I knew approx date I bought it. Is there a way I can check my
machine to find out what date I updated from Win98SE to WinXP?
I have another XP upgrade that I bought to update my laptop, could I use it
to reformat my desktop? If I can would that be legal?
Don