The whole procedure should take about 30 minutes. This procedure works for Windows 7, 8 and 8.1 and you won’t need to reinstall your software and apps.
This post will show you how to downgrade / change Windows edition from Enterprise to Professional in a couple of steps.
If you don’t need the Enterprise features, you can decided to downgrade your Windows 8.1 Enterprise edition to Windows 8.1 Pro to have the free upgrade to Windows 10. You want to install the latest Windows version to have the new OS features but you found out that one of your computer is running Windows 8 Enterprise edition which is not covered by the free Windows 10 upgrade.