Microsoft said in a support document that Windows 10 users who upgrade to Windows 11 will have 10 days to easily roll back that update. After that 10-day grace period you "will need to back up your data and do a 'clean install' to move back to Windows 10," the company said, though it didn't explain why that was the case.

ExtremeTech spotted this information about rolling back from Windows 11 in a PDF that Microsoft provided to MSI and, presumably, other PC manufacturers. The report said that moving back to Windows 10 during that 10-day period will be as simple as going to Settings > Update & Security > Recovery and selecting the build of Windows 10 you want to restore. Unlike performing a clean install, this process should leave all of your files intact without requiring any additional steps.

This limited rollback window is actually more permissive than major updates to Windows 10. Installing one of the biannual updates currently removes system restore points associated with previous versions of the operating system; having 10 days to downgrade from Windows 11 to Windows 10 without having to perform a clean install is an improvement. (So long as it's made clear to consumers when they update rather than being communicated in a document sent to manufacturers.)

Windows 11 is expected to debut later this year on new devices, but Microsoft has indicated that PCs already running Windows 10 won't be able to upgrade until early 2022. The company reiterated that point in the PDF shared by MSI. "The upgrade rollout plan is still being finalized, but for most devices already in use today, we expect it to be ready sometime in early 2022," it said. "Not all Windows 10 PCs that are eligible to upgrade to Windows 11 will be offered to upgrade at the same time."

That means the easiest way to use an official release of Windows 11 before 2022 will be to purchase a new device. Microsoft said that "PCs with Windows11 pre-installed will be available later this year" and that "many different manufacturers will offer a variety of devices that will run Windows 11" to be sold by "a broad selection of retailers." Those devices won't have an easy way to shift to Windows 10, however, so patience and impatience will both have their own benefits and drawbacks.

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