One of the features Windows 10 offers is the option to roll back to your earlier OS installation if, for some reason, you either don't like or have compatibility issues with Windows 10. While this isn't an option that many people take, it's going to be important if you find out that a certain software package doesn't work correctly with the operating system. One reader, for example, pointed out today that he's going to need to fall back to Windows 8.1 until SolidWorks adds support for Windows 10, which isn't currently expected until mid-October. Remember, however, that you've got just 30 days to jump back -- after that point, Windows 10 will no longer offer the option to fall back to the older version.
If you've jumped to Windows 10 and find yourself encountering bugs or other problems, it may be wiser to downgrade immediately rather than waiting to see if patches are available before the timer runs out. This may be true, even if the software company in question has promised to deliver a patch update within the next month. Despite the best efforts of software companies, such patches can fail or get bogged down in hardware testing, and you won't want to have a critical component of your workflow broken because a timer ran out.
Falling back is as simple as opening the Settings menu, choosing Update and Security, then picking the Recovery option. When you do, you'll see a screen like this one:
Choose Go Back to Windows 8.1 / 7, depending on your original operating system, and Windows will begin the rollback procedure. There's no word yet on whether or not users who roll back can still reinstall Windows 10 at a later date. There's also no information on whether or not you can reinstall an old copy of an OS once you've upgraded that version to Windows 10. When Tom's Hardware took this question to Microsoft, the company responded that some hardware changes can invalidate a Windows 10 upgrade license, and it wouldn't answer if customers could re-use old activation keys to reinstall previous versions of their own software after installing Windows 10. This last could be a problem for users who upgrade to Windows 10 but forget to drop back to an older version before 30 days have passed, which is one reason we're calling it out early in the life cycle.
As things stand, it's not clear if you can fall back to an old OS installation by doing a new, from-scratch reinstall using your original CD key or not. It's also not clear just how much hardware you can change without triggering the need to contact Microsoft's customer service to manually reactivate the operating system, Microsoft only states that a change must be "meaningful."
If you're concerned about losing access to your Windows 10 key, or if you simply want to make a backup of it in case something goes wrong, the freeware utility ProduKey(Opens in a new window) can be of assistance. The utility, which can be downloaded here, will record the product keys of any Microsoft application on your system.
I've blanked out the license keys themselves, but you can see how the software functions. We recommend making a back up of all license key information, just in case you end up in a situation where you have to either reinstall or contact Microsoft for additional assistance. In the meantime, we recommend testing all of the applications and games you typically use/play before deciding whether or not to stick with Windows 10. Don't get caught off-guard if a critical app doesn't work, and don't wait until the last minute to check the situation.
