If you have installed a preview version of windows 7 ultimate e g.
Windows 7 ultimate to windows 7 professional downgrade.
If windows 10 just seems unstable you ll want to go back to your previous version of windows and wait a while longer before attempting an upgrade.
This is because the multilanguage functionality is exclusive to windows 7 enterprise and is not available for a professional edition.
Or if you d just rather hang onto windows 7 for a while longer you can downgrade.
The trick should also work if you intend to downgrade from higher edition of windows 7 to lower edition such as from windows 7 ultimate to windows 7 professional or from windows 7 professional to windows 7.
Next insert your windows installation disk select upgrade and your windows 7 enterprise will be downgraded to the version you have specified.
A windows 7 ultimate installation can normally not change into a minor version of windows 7 home premium or professional.
7 finally click the go back to windows 7 and to begin the downgrade process.
Note a windows 8 customer who has multilanguage functionality cannot downgrade to windows 7 pro or to windows xp pro.
Unfortunately unless you went through an upgrade process there is no safe way to revert back to older editions.
Anyhow i found a trick to downgrade windows 7 ultimate to professional easily without the new installation.
Download windows 7 downgrader.
Continue with usual windows 7 installation procedure and let windows upgrade downgrade from windows 7 enterprise to target version.
If an important program or hardware device you use doesn t work on windows 10 you ll want to downgrade.
Knowing you have windows 7 enterprise tells me this.
Beta release candidate build 7100 or rtm build 7600 and want to install a cheaper version windows 7 home premium or professional the installation is refused.
The time to complete the process should only be several minutes but the time will vary from computer to computer.