How to Select Windows 7 Version on Install

Here's a quick tip for making sure you can select which version of Windows 7 you want to install on a system. This is especially useful if you have multiple keys for different OS versions (Home Premium, Professional, etc.)

If you look in the /sources/ folder (either in the .iso or on the media), look for a file ei.cfg. If this file does not exist, the Windows setup will allow the user to select the OS version to install. If the file exists, it will specify which version the installer will use by default. The file will look like:

[EditionID]
Ultimate
[Channel]
Retail
[VL]
0

From here, you can either edit the file to use your desired version by default, or simply remove the file to give yourself the option later. Doing either of these is quite simple if the iso had already been copied to a bootable USB. Otherwise, you will need to use an .iso editing tool to make the change. Good luck!

Source

Downgrading Versions of Windows 7

Have you ever needed to downgrade a version in Windows 7? Let's say you have installed Windows 7 Professional (or Ultimate?) on a system, only to grab the key and realize it is a key for a lesser version of the OS (say, Windows 7 Home Premium.) I ran into this very situation today. And downgrading to a less-fully featured version can be difficult to figure out without some help. Thankfully I found just the right hack I needed to make it work, and it is a relatively simple and painless process. I borrow shamelessly from aquasystems :


here is a “simple” hack which allows you to embed the downgrade procedure in Windows 7.

Click Start.
In the Search Box, type regedit and press Enter.
Navigate to this registry key: HKEY_LOCAL_MACHINE\Software\ Microsoft\ Windows NT\CurrentVersion

In the right pane, click EditionID and ProductName and give them the value which corresponds to a lower Windows 7 edition. Here is an example:

Windows 7 Home Premium (downgrade from Windows 7 Ultimate to Windows 7 Home Premium)
EditionID: HomePremium
ProductName: Windows 7 HomePremium

Start your Windows 7 installation by inserting your Windows 7 Disc.
Now, Select Upgrade as type of installation. Follow the instruction on the screen.
Reactivate your operating system.

Voila! I give you, the Windows 7 downgrade. It worked like a charm. Thanks aqua!