Hello! My name is ***** ***** I will be the expert assisting you this evening. I see that you would like to roll back your operating system from Windows 10 to Windows 8.1. Give me just a moment. I should be able to assist you with this.
When did you install Windows 10?
I need to know which version of Windows 10 was installed. To see what version of Windows 10 your PC is running after you upgrade, select the Start button, then select Settings > System > About. Let me know if it is version 1511 or 1607.
Luckily, with either version you have 30 days or 10 days to roll back to your original version. All you need to do is go to Settings > Update & security > Recovery. You will have an option to "go back" to Windows 8.1. This should take you back to everything as it was before you upgraded, all of your files and photos, etc. in tact.
If "go back" isn't available, then you will have to do a factory reset. This will erase all of your personal information, unfortunately, so if you have anything to save, do it from Windows 10 before you do this. To do a factory reset, you can go to Settings > Update & security >Recovery > Reset this PC > Get started and look for Restore factory settings.
The only other way to do this, is only if you have your product key from Windows 8.1 and you made recovery media, which you still should be able to do from the Recovery section. I don't foresee you having to do this but I wanted to give you this information any ways.
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