Cannot connect to itunes. Podcast, ok; itunesU, ok; computer ok--same network as ipad

My iPad says "cannot connect to itunes store", no other error messgae. I can connect to podcast and itunesU, but not the store. I can connect to itunes store on my pc (win7). The things have changed: was using a temp apple id without a credit card for a month. Now, have a real id with credit card but still cannot connect. I thin itunes turned me off?