My Apple id hasn't changed, and I restored my library from time machine. But when I try to play or download podcasts I get this message. This is true of all podcasts. I AM able to access my music. Even purchased music.
Okay, the library was on an external drive (where it's always been) but now that seems to cause problems. I've been able to subscribe to podcasts after creating a NEW itunes library. The next thing is to take all my music files from that other drive and "automatically add to itunes" I'll move the library later.