Upgrading from Windows 7 Ultimate RC to Windows 7 Professional?

I don't believe it's possible. Back your data and such up and prepare to wipe it clean. Do a quick search of the W7 forum here, there are some threads on it. MS also has a few things on it as well.

I was looking at Microsoft Technet. They said it was not possible.
http://technet.microsoft.com/en-us/library/dd772579(WS.10).aspx

What isn't disqualified is using your Upgrade disk from with in Windows7 Enterprise.
Here is the link
http://technet.microsoft.com/en-us/evalcenter/cc442495....

You will have to install and activate Enterprise first.
If this works you are home free!

Edit: You will have to choose custom when installing, ( again if it works)

nope

By that do you mean I can do a fresh install with my upgrade disc? How exactly do I do that? If you could tell me or give me a link to the step by step method, I would love you forever.

@knotknut: Thanks for that info! I will try that if all else fails.

To use the upgrade disk you need to have a previous activated OS installed, which is equal to or lower then the version you are upgrading to.
So you need Vista Busines or lower, or any version of XP.

So that means I'm pretty much screwed?

If I install it via Windows 7 Enterprise, can I get rid of Enterprise after the install? Also, I have 2 1TB HDD's in my rig. One is for my OS and non-important files, and the other is for my important files. Could I move all my files onto my one HDD, remove it, then do the install, and add my other HDD back in after I'm done? Will all my data be okay by doing it that way?

Thanks for all the help so far guys.

Bump.

Wow, what a difference, i installed windows 7 pro after using windows 7rc(i did a clean install not a upgrade), funny thing happened, my motherboard drivers for p35 ds3l didnt work from the disc like they did in rc, freespace is not compatible(was in rc), office xp is not compatible(was in rc), and to make things worse, i tried to restore a bakup from syncback and i cant because a profile doesnt exist(no more free software for backup gonna go with acronis true image, so i restore to any computer), all in all it's bee pretty miserable.

HOW DO YOU DO A CLEAN INSTALL? Can you do it with the Upgrade disc? Could someone explain it to me PLEASE? I'm sorry, but I'm relatively new to this and Google is turning up nothing for me. PLEASE HELP!  

Bump.

Format your hd, which erases everything, andinstall fresh operating system, drivers, programs, etc, you wanna hit custom when the option comes up on w7 disc, then format, and the rest takes care of itself.

Thank you for that.  

I will try that. Should I disconnect my other HDD's first so I don't lose any of my data, or can I leave them hooked up? If I do disconnect them, after the install will it be easy to recover my files?

you can downgrade your RC to pro or any other version with a simple registry tweak.

hklm/software/microsoft/windowsNT/current version. change
key <ProductName> to whatever version you want to upgrade to

hklm/software/microsoft/windowsNT/current version. change
key <EditionID> to whatever version you want to upgrade to


http://windows7forums.com/windows-7-installation-upgrad...