Upgrade Windows 7 from Release Candidate or RTM version

Many of you have been running Windows 7 since the first Beta and moved onto the public Release Candidate. They were offered to the general public as a free 'beta' or taste test of the new OS.
Windows 7 is, in my opinion, a huge step up from Vista in virtually every area.

But as you know - or should know, The RC expires in March of 2010! By that time you will have had to have installed the retail version or you will be warned by the machine shutting off every two hours. When the free Release Candidate begins to expire you can't even do an upgrade install of Windows 7, you will have to either re-install Windows Vista first, or buy a standalone version of Windows 7!

So let's get with the upgrading.
First let me point out that a 'fresh/clean' install is almost always the best way to go. However there are times when an upgrade makes a lot of sense. Such as when you had to 'tweak' a special driver, or have massive amounts of applications installed and uniquely configured, or simply just have everything 'just the way you want it'.

A note on Windows 7 pricing:
The Windows 7 Family Pack, consists of 32-bit and 64-bit Windows 7 Home Premium Upgrade media Setup discs and a single product key which can be used to activate three copies of the OS on three different PCs! The Family Pack costs $150, or just $30 more than a single copy of Windows 7 Home Premium Upgrade. It's kind of a no-brainer to me.

OK on to the upgrade process:

1. Copy of all of the files from the retail disc to a folder on your hard drive I called it "Win7Upgrade" 
2. Navigate to and then open the "sources" directory in that folder, and look for a file called "cversion.ini".
3. Right-click and choose 'open with' and choose 'Notepad'. You may also launch Notepad and choose File>Open and select that file.
4. Change the number 7233 to read 7000 (you're telling it the minimum version that's allowed to upgrade). Save it.

Right, now you're almost there.
One more thing you may have to do.

When doing an upgrade MS limits you to what 'type or flavor' of the OS you can upgrade to.
Example; Vista Home Premium can only be upgraded to Windows 7 Home Premium, Windows 7 RC(and therefore 'Ultimate') can only go to Windows 7 Ultimate etc.
BUT HERE IS THE GREAT PART!
That is not entirely true!
You can upgrade to a different version with a simple registry adjustment.

Open a command promt on your Vista or (Windows 7 Release Candidate) machine and type in:

Regedit

Navigate to HKLM(HKEY_Local_Machine)Software\Microsoft\Windows NT\ CurrentVersion

Change EditionID on the reg key from "Ultimate" to "[youreditionhere]"
and
Change ProductName on the reg key from Windows 7 Ultimate to "Windows 7 [youreditionhere]"
(minus the quotes of course)

Example:

EdittionID Professional

ProductName Windows 7 Professional

Close the registry editor, restart and do your install.
I have used this trick to upgrade some of our corporate Netbooks that came with Windows 7 Starter to our Volume License version of Window 7 Enterprise.

Remember you will have to have a valid install key/license for what ever version you install AND you will have to activate it. You won't be able to use the same key on a bunch of machines.
That's it.

Maximum PC has an article that details some of the steps above in a little more detail. Before you try any of these tricks you should check out this article too.

They also have a fantastically easy to walkthrough of how to boot and install from a USB.

Paul Thurrott's SuperSite for Windows has a great article on how to do a Clean Install Windows 7 with Upgrade Media

Well that's all.
Hope you find this information usefull.
Here is some great stuff on utilizing many of the features in Windows 7. I have also put a 'short-cut' image that can be printed out too.

Happy computing
Peace