Upgrade steps for transitioning from Windows 8.1 to Windows 7
Sure, the information isn't that simple, right?
You need to purchase Windows 7. 8.1 Pro OEM qualifies for downgrade privileges to 7 Professional.
It's that simple.
Essentially, you just remove every file from your HDD or SSD with Windows installed and then set up the fresh version of Windows.
There are no guidelines here.
Formatted text for clarity
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