Downgrading to a lower SKU is not possible, from what I know. Windows 7 Enterprise is a superset of Professional, so your only option is reinstalling, from my knowledge.
The same thing is true in Vista, you can only upgrade, not downgrade (Home Premium to Business was allowed, the other way around was not allowed).
Edit: here's the official response from Microsoft, courtesy of Mary-Jo Foley:
So the answer is no, you can't use WAU
to move from Windows 7 Enterprise to
Windows 7 Professional because that
would essentially be a downgrade.
Windows 7 Enterprise is just like
Windows 7 Ultimate, all of the
features are part of the SKU.
What WAU is meant to do is allow users
to add more features to Windows 7 by
upgrading to a higher edition without
having to go through a time-consuming
re-installation process. There are a
variety of scenarios in which a user
may choose to upgrade after the
initial purchase, including:
- A consumer purchases a PC pre-installed with Windows 7 Starter
and wants to turn it into the best PC
for entertainment.
- A customer purchases Windows 7 Home Premium, but realizes they need
Professional features including Domain
Join, which provides the ability to
add the computer to a company or
school network.
- Someone
purchases a PC pre-installed with
Windows 7 Home Premium and wants to
experience of all of what Windows 7
has to offer with Windows 7 Ultimate.
There's something weird about the Netgear FTP server. I can't dowload the files using my browser, but it works fine with Command Line FTP.
So, I downloaded the files as follows:
Open a Command Prompt, cd
to the directory where you want the files and enter the following command:
ftp downloads.netgear.com
You should see:
Connected to downloads.netgear.com.
220 downloads.netgear.com NcFTPd Server (licensed copy) ready.
User (downloads.netgear.com:(none)):
Enter anonymous
as the user and blank (or your email) for the password.
At the ftp>
prompt enter the following commands:
bin
get /files/sc101t_firmware_1_1_3.bin
get /files/scm_3_0_6_setup.exe
After each get
you should see something like:
150 Opening BINARY mode data connection for scm_3_0_6_setup.exe (7366046 bytes).
226 Transfer completed.
ftp: 7366046 bytes received in 124.42Seconds 59.20Kbytes/sec.
When you've finished just type quit
at the ftp>
prompt.
If that doesn't work, post a comment and I'll upload the files to one of the many file transfer sites.
Best Answer
Windows 7 Type
winver
in the start menu, click on the Microsoft Software License Terms and go to section 3FVista home limit is 5 and the others are 10 -
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