http://techpp.com/2009/11/11/download-windows-7-iso-official-direct-download-links/

BTW, I used an 8 GB key but 4 GB would have been sufficient.

Cheers,
DH

After making an ISO of my Win7 Pro DVD, I followed the directions here:
http://arstechnica.com/business/news/2009/12/-the-usb-flash-drive.ars/

This allowed me to make a bootable USB key with an image of the Win7 DVD. More importantly, since it was on USB key, I was able to easily change it – for example, delete the ei.cfg file to make it non version-specific.

I upgraded my Vista Home Prem to Win7 Home Prem, then used “Anytime Upgrade” to go to Win7 Pro thereafter.

Thanks again, all!!
DH

I have a few clients who purchased Windows 7 Pro who wanted to upgrade from vista home premium. For this procedure I started with the x15-65804.iso and the install key. Use 7zip or your favorite file manager to extract the iso to a directory-(you will get the same installation folders if you burn the iso to a disk and then back to your computer but 7zip saves the step). You can also run the .exe install option to create an install directory with the same structure as the install disk.)

Once completed, open the ‘sources’ folder in the root directory, then look for the ei.cfg file. Open it with notepad++ or your favorite editor. the text appears as:

————–
[EditionID]
Professional
[Channel]
Retail
[VL]
0
————–

Change that to:

————–
[EditionID]
HomePremium
[Channel]
Retail
[VL]
0
————–

just change Professional to HomePremium, whatever your version. Save the file.

Put the whole expanded windows installation media folderfrom above onto the target computer. Install windows from the setup file in its root folder. You can make another iso and burn to/install from disk if moving the folder onto the target machine is not possible.

My last install was to a Dell Inspiron 1521 with Vista Home Premium and a typical profile of OEM software and MS Office 2007. From ‘Install Now’ to 7 Home desktop took me about 170 minutes, though your mileage may vary.

When prompted to enter an installation code, -do not use your key- just choose next. Windows will proceed and restart. Your pro code won’t work anyway, but as of this writing, windows restarts and presents a 7 Home Premium Screen.

From reading another set of directions I thought the logical next step would be to run the setup file again, this time with the original software with Professional in the ei.cfg file. Not so…once I had 7 installed, it directed me to instead run the ‘anytime upgrade’ program installed with 7 Premium.

I opened the anytime upgrade and pasted the pro 7 key code into the window. That was accepted, and upgrade from that paste to a Pro desktop took 25 minutes. All programs and settings were intact.

Apparently nothing illegal or unethical is required here either. If you feel uncomfortable changing the ei.cfg file you could accomplish the same thing by using a 7 Home Premium Disk in the first phase and then just doing the anytime upgrade with your genuine key…all done. As a system builder you don’t have to maintain several versions of install disks like with XP-there is just the one disk and the one ei.cfg file.

I took a tour of the program files before this procedure and made sure none of the ‘extra’ OEM programs like a browser error redirector made it into 7. The only program that the upgrade advisor told me was definitely not going to transfer was a Dell modem driver manager. Apparently any incompatible programs are eliminated during the upgrade, but I would stop, uninstall, and then resume the upgrade if directed just to be sure.

This would apparently work for any scenario not supported by Microsoft’s official path as long as you have an install key and media. I hope it helps you as much as the other posts helped me.

If you look around on google, I think there is a tool out there that will do it all automatically.