Q: iTunes and Software Update can't connect to the servers

Hello

Mac Pro 3.1 with OSX 10.9.5

iTunes and Software Update can't connect to stores. In iTunes I get errors like:

iTunes cant verify server identity for init.itunes.apple.com (or xp.apple.com)

I can't connect to iTunes Store. Error (-9807)

of course network is ok, I cant browse every site I want and from another PC on the same LAN I can connect to iTunes with my acount.

Any suggestion?