Last week my Missus had the same problem. She upgraded her Windows 8 to Windows 10, only to find she couldn't get on the internet through W10. She called MS Support and it was determined there was a problem (I wasn't at home at the time, and she couldn't explain what the problem was) and the bloke suggested "downgrading" back to W8. Once that was done, she had her internet access back on that PC. So it might just be worthwhile giving them a call, even if it means being on hold for 4 days!!
