Hack to In-Place “Downgrade” from Windows 7 Ultimate or Professional to Less Premium Editions
Windows 7 does not allow users to “downgrade” or convert from a more premium and more expensive edition to down-level, more basic and less expensive edition. For example, it’s impossible to downgrade from Windows 7 Ultimate to Windows 7 Professional or Enterprise, or from Windows 7 Professional to Windows 7 Home Premium or Home Basic.
Windows 7 SKUs or editions have a hierarchy as below:
Starter -> Home Basic -> Home Premium -> Professional -> Ultimate
Upgrade is only possible one-way from the lower edition to higher edition of Windows 7, and not the other way round. If user attempts to perform an in-place upgrade to downgrade to lesser edition of Windows 7, an error similar to below will be displayed at compatibility report:
Windows 7 Ultimate cannot be upgraded to Windows 7 Home Premium. You can choose to install a new copy of Windows 7 Home Premium instead, but this is different from an upgrade, and does not keep your files, settings and programs. You’ll need to reinstall any programs using the original installation discs or files. To save your files before installing Windows, back them up to an external location such as a CD, DVD, or external hard drive. To install a new copy of Windows 7 Home Premium, click the Back button in the upper left-hand corner, and select “Custom (advanced)”.

The refusal of Windows 7 to downgrade causes several groups of people some headache, especially when user doesn’t want to lose and wipe off existing programs installed. For example, users who installed Windows 7 Ultimate during beta or release candidate phase of Windows 7, but now acquire a Windows 7 Home Premium or Windows 7 Professional license. The situation can also apply to user who installs Windows 7 Ultimate or Professional edition, but now wants to go legit by buying or being given a gift of Windows 7 Home Premium license. End-users also have to go through the hassle of backup all data files when clean install is required.
Microsoft probably forbids downgrade for a reason, such as possibility of corrupting or messing the operating system and complexity involved in such downgrade. For user who must perform in-place downgrade, there is a workaround trick that can force Windows 7 setup installer to allow “upgrade” or downgrade from uplevel edition of Windows 7 to downlevel version of Windows 7, while retaining all installed application software, drivers and migrating all documents, music, video, shortcuts, bookmarks, favorites, and personal data files or settings.
- On existing Windows installation, run Registry Editor (RegEdit).
- Navigate to the following registry key:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion
- In the right pane, change the value data of EditionID and ProductName to reflect a minor version of Windows 7.
For example, to fool OS to think that it’s another edition of Windows 7, hack the registry key to the following values as below:
Original Windows 7 Ultimate registry valueWindows 7 Home Premium (allow Windows 7 Ultimate or Professional to Home Premium downgrade)
EditionID: HomePremium
ProductName: Windows 7 HomePremiumWindows 7 Professional (allow Windows 7 Ultimate to Professional downgrade)
EditionID: Professional
ProductName: Windows 7 ProfessionalNote: The ProductName and EditionID should have the same name with the Windows 7 operating system name displayed during OS selection on the installation DVD. Some Windows 7 installation DVD may use “Windows 7 Home Premium” as OS name. See the hack to enable Windows 7 OS edition selection during setup by disabling ei.cfg to create universal Windows 7 installer ISO.
- Start Windows 7 installation by inserting Windows 7 DVD disc into disc tray, or mount the Windows 7 ISO image into a virtual drive.
- Select Upgrade as type of installation. Then, continue to install Windows 7 as per normal.
For user who decided to upgrade from Windows 7 Beta or Windows 7 RC release, the Windows 7 upgrade paths also does not support direct upgrade any prerelease versions of Windows 7. However, an easy hack of modifying cversion.ini can enable direct upgrade to Windows 7 final from Windows 7 RC or Beta.
One last note is that after the “downgrade” of Windows 7 installation, the operating system must be reactivated.
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- How to Select Any Edition or Version (SKU) of Windows 7 to Install From Single Edition DVD Disc Media or ISO
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- How to Downgrade from Windows Vista Business or Ultimate OEM Edition and Install Windows XP Professional Without Extra Charge
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January 19th, 2010 08:57
did the job as expected. thanks
January 5th, 2010 00:14
(continued from previous comment)
Good news- I was able to switch from Windows 7 Ultimate to Windows 7 Professional after all. I took a cue from CJ and changed the registry values to say “Business”, and during installation I also told it not to download updates for the installation (when it asks at the beginning of install). Not sure which of the two made it work, but one of them did.
January 4th, 2010 22:28
Made the registry changes to “Professional” and “Windows 7 Professional”, and tried to downgrade Windows 7 Ultimate 64bit to Windows 7 Professional 64bit. It got to the very end and then said that it couldn’t be completed, and rolled back to Ultimate. When it booted back up, it showed this error: http://imgur.com/VQ72K
December 18th, 2009 12:11
I could not get the way described to work using an inplace upgrade from Vista Ultimate to Windows 7 Pro.
However, I found that changing the following would allow an inplace upgrade.
From
EditionID: Ultimate
ProductName: Windows Vista (TM) Ultimate
to
EditionID: Business
ProductName: Windows 7 Business
December 18th, 2009 00:20
Didn’t work for me. Tried to change Vista Ultimate to Vista Professional, then install Windows 7 Professional, but it wouldn’t accept the change. Still thinks I am running Vista Professional. Checked the Registry, and the change was there, but something else is telling Win7 that Ultimate is installed. Any ideas?
December 14th, 2009 11:02
This neat trick didn’t work for me. Currently running Vista Ultimate 64, tried downgrading to Windows 7 Home Premium. Failed once, put a space in the product name field and failed again the same way. Got to where it was copying 700,000 files or so, left, came back and vista was running again with a message that said it wasn’t compatible… Windows 7 upgrade advisor would never run before, but after the first failure it does. The hack is in place but the upgrade advisor says I am running Vista Ultimate.
December 12th, 2009 02:50
Brilliant! Worked fine, although the upgrade process is sloooow (100 minutes!?!? on a high-spec PC)
Win 7 Enterprise RC –> Win 7 Professional RTM.
Thank you!
December 7th, 2009 07:24
Dmitry
For user who decided to upgrade from Windows 7 Beta or Windows 7 RC release, the Windows 7 upgrade paths also does not support direct upgrade any prerelease versions of Windows 7. However, an easy hack of modifying cversion.ini can enable direct upgrade to Windows 7 final from Windows 7 RC or Beta.
You need to upgrade to the RTM version first – ver 7600 of Windows.
November 27th, 2009 10:00
If I am downgrading from W7 Professionsal to W7 home premium, what edition should I tell the system I have. Hope Premium is already the base system? Can I tell the system it is Vista when it is actually W7?
November 25th, 2009 17:39
Is it possible to downgrade from a 64bit Ultimate version to 32bit Professional using this method?
November 20th, 2009 08:55
Worked PERFECTLY upgrading from Vista Ultimate to Windows 7 Home Premium. You da Man!
November 15th, 2009 10:34
thanks.
Your steps worked fine.
I was getting so stressed with this problem after upgrading using the msdn dvd and not being able to downgrade.
The weird thing is that i dont recall entering a key during the msdn upgrade, and for some reason the upgrade took me from vista oem home premium to ultimate(not home premium)… but then no way to go back to oem home premium win7 when i finally got the dvd upgrade from the manufacturer. what a waste of time…
November 11th, 2009 13:49
pyro42, yes it does work downgrading vista business to w7 home premium. I just did it, had no problems at all and days later I detect no issues.
I used:
EditionID: HomePremium
ProductName: Windows 7 HomePremium
November 9th, 2009 23:26
Worked perfectly for me.
I went from Windows 7 v7100 (evaluation version) to Windows 7 Home Premium using the Registry and cversion.ini tricks. I used a Windows 7 upgrade disk that I got free from Microsoft when I purchased an OEM copy of Vista home Premium. I now have a fully working, validated W7 Home Premium instalation.
November 5th, 2009 16:11
I’m going to be trying this with Vista ultimate > Windows 7 upgrade soon, I’ll post the results here when/if it works.
November 5th, 2009 03:55
FYI: Technically Enterprise is just the same as Ultimate. Licensing model is the only difference.
November 4th, 2009 21:56
it also works professional -> ultimate upgrade
i tried with an image of win7 and it didnt give an error
November 4th, 2009 06:44
OK, I figured out what as the problem. There’s a vital note: for Home Premium version only ProductName should have space between words. EditionID MUST be written in one word. So the final edit is the following:
EditionID: HomePremium
ProductName: Windows 7 Home Premium
November 4th, 2009 04:53
Didn’t work for me. It still says I have Ultimate and it can’t be upgraded to Home Premium.
Currently I have Windows 7 Ultimate, Build 7100 (RC).
November 4th, 2009 02:36
what are the chances of this working to inplace downgrade from windows vista business to windows 7 home premium?