'Upgrade or Full' What is the difference..

foojoo said:

Hi Bob,
Thanks so much for the info. But one quick question.. This trick was found on Vista's upgrades, right? Who's to say that the upgrades shipping in October will actually still allow this? Does anyone have like a pre-shipping copy of the upgrade who would be able to confirm that it stills works?

Thanks in advance!

If you have a CLEAN install the upgrade will not function that way... only a OEM or RETAIL Key... per instruction in the UPGRADE Manual sent by MS.

foojoo said:

I guess my question boils down to:
Could I theoretically buy a XP home edition OEM Key and upgrade it to 7 Professional? I heard of upgrades being restrictive to editions (pro->pro etc.)

It's probably not even necessary to own Windows XP. But it's just my guess, and I suppose it would be cheating to use the Windows 7 upgrade media when you never owned a copy of Windows to begin with.

I don't know that anyone will know the real answer to your question besides Microsoft themselves.

I used an upgrade disc a few years ago and did clean installs with it, don't remember for sure, I think it was XP. At some point it just asked you to put the disc from the required OS in the tray to verify. That was it. The upgrade page on newegg says all copies of XP and Vista qualify you for the upgrade.

Good info dmb219. +Rep

Here's your answer:

* Running Windows Vista?
* If you have Windows Vista, you can purchase Windows 7 Upgrade versions. You can do a clean install (back up your files, clean install, and reinstall your applications) or an in-place upgrade (Windows 7 installs over Windows Vista).

* Running earlier versions?
* If you have Windows XP or Windows 2000, you can purchase Windows 7 Upgrade versions. But you must back up your files, clean install, and reinstall your applications.

Bottom of this link:

Windows 7 - Buy and download from Microsoft Store

Upgrade versions are for people that own a previous qualifying MS operating system. (XP or Vista) Full version is for people who don't own one. (Let's say someone who get's their first computer and doesn't have a licensed copy of XP or Vista) In a sense it's like $500 customer loyalty rebate on buying a new car from the same manufacturer as your current one.
Some of the other posts about installing twice and and the disc swap (albeit last I remember the later of which was quite some time ago) are both correct too. Since you can't upgrade from XP you're have to clean install it. I think a single install and then activating would work fine too.

Another option when installing the upgrade media as a clean install.

Install it once without a key, as a clean temporary install, using the DVD to boot. Go all the way until the desktop. Reboot.

Boot the DVD again, use the upgrade key this time, then format the partition (under advanced options) that you installed the temporary copy to. You can now install a clean copy to this partition, using the upgrade key, and it will activate merrily.

You can do this 2nd step regardless of what the original install is; so if you have an xp install, a vista install, you can do this 'format and clean install' into its partition (or a 2nd new partition alongside) using the upgrade key, without having to do an inplace upgrade, along with all the cruft that accumulates.

Clean install from upgrade is fully explained and covered in post 15 and 11.

To save having to read the whole thread, Here it is ( with screenshots) again:

Clean Install From Upgrade Vista - Vista Forums