s.ytimg.com resolves to static.cache.l.google.com. Try running "ping s.ytimg.com" and see what IP address it resolves to for you. This is likely an array of several different servers, and the IP you're getting is unreachable for some reason, but the IP it tells me is a working one. I get 74.125.7.31. If what you get is a different address, run "notepad windows\system32\drivers\etc\hosts." and add the following:
Get to a command prompt, type the stuff between the quotes. then insert the stuff in the code box into the file once notepad opens it. then save and close the file. Actually you might need "C:\" in front of windows so that it says "notepad C:\windows\sys..."
Sorry about that, I learned a long time ago, one of the worst things a computer tech can do is give a syntax error to a non-technical user. Because then you get to spend the rest of the day figuring out why what you recommended didn't work, and how much damage did it cause.
Anyway I expect what you're experiencing is transient and will clear itself up pretty soon.