"Remote device or resource won't accept the connection"

Hi all,
Back again with another Windows 8 problem My Dad's HP computer with Windows 8 was all working fine up until yesterday, but now for some reason, it can't access the Internet, even though it is connected (my laptop is connected to the same network and can access the net with no issues). I tried running a troubleshooter and I got a message saying "Remote device or resource won't accept the connection" though it didn't offer any solutions. I have tried resetting both the computer and the router and it has not made a difference. He has Kaspersky anti-virus and to my knowledge, has not installed/uninstalled any software recently, so I can't think of anything that would have caused it.

The only thing I could think of was that maybe the cable running from my router, through the roof to their computer in the other room may have somehow failed or become damaged, but in that case I would have thought it wouldn't be able to find the network at all (it still says it is connected to the Internet). Since testing this would involve climbing up into the roof etc and both I and my old man have dicky knees, I was hoping someone might have suggestions for what could be causing the problem, or how I might be able to fix it with (relative) ease. Thanks in advance

(P.S. Sorry if this is in the wrong section or has already been answered, if this is the case, please just point me in the right direction)

hmm I messed around on the computer for a while and for some reason the internet is now working perfectly. It seems that somehow sharing between networks had been turned off, and once I fiddled with that, it was up and running again.