If your PC is not offering 8.1 I'd never force it. I'm going to write that getting it without the offer is too dangerous. Even if you are offered it, a few folk forget to backup what they have and have lost it all. Don't be like Frank!
Bob
I have an option to update to Windows 8.1 copyright Microsoft 2013 at work, but my laptop is using Windows 8 copyright Microsoft 2012, and has no option to update.

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