Expert Opinions Needed - Downgrade Win7 Version

Discussion in 'Windows 7' started by Bax!, Sep 8, 2009.

  1. Bax!

    Bax! MDL Member

    Jul 29, 2009
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    As we all know the MS official story when it comes to UPGRADES for Win7 is that in place upgrades for Beta to RC to RTM is not possible - MS says you must clean install.

    We all know now that this is rubbish and with a simple alt to an ini file you can UPGRADE any previous version of 7 to RTM.

    Likewise, you can perform a legitimate "inplace upgrade' by using a different key for a higher version to convert your current version to a better 'higher' version... eg: Home Premium to Ultimate simply with a change of key...

    DOWNGRADE - Here's the question... :)

    If I have Ultimate installed, does anyone know of a tweak, a file change, a reg edit or anything - that will allow me to DOWNGRADE from Ultimate to Professional??

    Obviously I am trying to avoid having to do a total reinstall of the OS and all apps.

    MS says some UPGRADES cannot be done and it is crap... they also say DOWN grades cannot be done.... is this true??

    Is there a fix to this problem??

    Thx :)
     
  2. urie

    urie Moderator
    Staff Member

    May 21, 2007
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    I don't think you can downgrade why would you want to any way always better with a clean install:)
     
  3. Bax!

    Bax! MDL Member

    Jul 29, 2009
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    I totally agree..

    But I want to challenge what MS says is IMPOSSIBLE - as we know, they lie through their teeth... is a downgrade really impossible, or is it that the tech gurus have just never really taking a look at this side of the software?? ;)
     
  4. urie

    urie Moderator
    Staff Member

    May 21, 2007
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    Well you can be the first to try it remove EI.CFG from sources folder and try install with premium key:D
     
  5. breeze

    breeze MDL Novice

    Aug 31, 2009
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    It is possible and I have done it. I went from x64 RC (Ultimate) to x64 Professional RTM, from there to Ultimate via Anytime Upgrade now I am back to Professional. Don't ask me why I upgraded to Ultimate in the first place :p

    Here's how I did it: You need your RTM files with the usual suspects (ei.cfg either removed or modified with the version you want to install, in cversion.ini file the minversion edited to sth lower than the current version, i have put 7000 there).
    Then in the registry go to local_machine -> software -> microsoft -> windows nt -> currentversion and set currentbuild and currentbuildnumber to 7100. Replace "Ultimate" in EditionID and ProductName with "Professional" (or whatever you wanna install or the name of a SKU lower than that).

    Now you can start the Win7 Setup and chose upgrade.
    This way it is possible to "downgrade" your version of Windows 7 without the need to reinstall everything again!
    And please no posts about how bad this is and a reinstall would be much better bla bla, don't care :)

    Have fun!
     
  6. Bax!

    Bax! MDL Member

    Jul 29, 2009
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    Haha.. fantastic!! I will go and try it and report back results - great find if it works - cheers! :D
     
  7. Bax!

    Bax! MDL Member

    Jul 29, 2009
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    You my friend are a legend!!!

    It worked perfectly - thank you very much!! :D


    ----------------------------------------------------

    For others interested... simply do the cversion.ini and ei.cfg trick as outlined by Breeze, then copy this into notepad, save as a .reg file and run..



    Windows Registry Editor Version 5.00

    [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion]
    "CurrentBuild"="7100"
    "EditionID"="Professional"
    "CurrentBuildNumber"="7100"


    Now run setup and select Upgrade.... to actually DOWNGRADE your Ultimate version to Professional version.

    :D :D
     
  8. jakk

    jakk MDL Novice

    Nov 2, 2009
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    Hey,

    I was wondering if someone could break this technique down a little for me.

    I have a machine with the 30-day Enterprise Trial MS released, i have subsequently obtained a legit copy of Professional which i want to activate withotu having to re-format and re-install.

    I understand the process by which the ISO is extracted to a USB stick, however i dont understand why the minversion ID in cversion.ini is set lower than the currentbuild and currentbuildnumber's on the machine installation?

    Id logically have thought that the minversion shoudl be higher than the "currentbuild"'s ID?

    Then again, its been a long day and i might just be being dense?

    All help and guidance is greatly appreciated!

    Cheers!
     
  9. jakk

    jakk MDL Novice

    Nov 2, 2009
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    By the way my cversion.ini contains only the following:

    [HostBuild]
    MinClient=7233.0
    MinServer=7100.0

    I take it It needs to be changed to

    [HostBuild]
    MinClient=7233.0
    MinServer=7000.0

    Cheers
     
  10. ciucca

    ciucca MDL Novice

    Aug 29, 2009
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    I can verify this works. I did it last night. I changed the minServer to 7000.0, and updated the registry.
     
  11. ciucca

    ciucca MDL Novice

    Aug 29, 2009
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    Changing the "ProductName" mention in the guide was not necessary, so I'm not sure about it. I would follow the procedure in this thread it definitely works.
     
  12. secr9tos

    secr9tos MDL Addicted

    Jul 28, 2009
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    So you make the installer believe it is dealing with another version... nice approach to the problem:D
     
  13. Unmade

    Unmade MDL Novice

    Aug 31, 2010
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    Sorry im getting up this old hot dog after so long, but i encountered a problem that only you guys seem to know if is possible to solve.
    I ran my pc on Vista ultimate for the past year and some months. Now i want to upgrade to 7 professional. Ofcourse the vista says its not possible to do it like that, cause decreasing the epicness even when going up a level is forbidden. I thought that maybe a good idea would be to first downgrade the Vista Ultimate to something lower, like homebasic and try to go with 7 from there. I dont rly know what parameters to place in the regedit to pull that off though. any suggestions? or maybe its impossible, or even maybe u have a different idea?
     
  14. micallan_17

    micallan_17 MDL Novice

    Jan 22, 2011
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    really nice post, old but very useful :)
     
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