will there be a problem.. upgrade windows 8 pro to 8.1

It'll refuse to install, since your copy of Windows isn't legitimate.

 

Upgraded the Lenovo Y410p (which replaced the constantly broken Y400...don't buy Lenovo!) to 8.1.....MEH! If you already use Classic Shell or similar and prefer Google to Bing (and who doesn't?), you'll be hard pressed to notice any differences at all between 8 and 8.1. If my laptop were a touch screen model and I used the "don't call it Metro" interface, perhaps I'd feel different.

I'd still hate Lenovo for putting me through the multiple repairs, then multiple swaps that took almost a full year though!

 

Upgrading laptops to 8.1 can be 'interesting'! I've optimised an Acer laptop for a friend, fine with 8, slow and a tad flaky with 8.1. He's kept it fairly clean & defragged (unusual for a non-techie user) so I surned off the indexing service and eye candy, and disabled a faulty USB device in device manager. Now runs better then before. If the Win8 install is not legit, I'd leave well alone.

 

That alone makes him sound shady--and increases the odds that he'd do something shady.

Is there not some way to verify the authenticity online? At least then you'd know, and you could move forward from there.

And, finally, since it is *ME* and everything , let me just point out that I have the same laptop--and mine has been happily humming along running Kubuntu Linux since I got it. I don't know how invested you are in window$ and its software, but if you're ready to dump it, I can personally verify there are no problems installing/running Kubuntu on it. You can burn an ISO and give it a try without changing anything on your hard drive, and then decide.

 

I already have a Start menu on 8. I boot into Desktop. I don't use Bing. And the laptop doesn't have a touch screen. I think I'll save my money for something really important - like a jelly donut.