Yeah I'm getting the same problem, when I try to play songs from my computer it only will play 30 seconds of it. I've never had a zune pass, before and I only started using the Zune software as of last night when 4.0 was avaible. It was working fine earlier today but now it only plays 30 second clips. Also, I'm getting an error on some song that says that the files can't be found or are moved, except for they haven't moved, and the folder is still being watched. I retold it to watch the folder and it either just plays 30 seconds or puts up a yellow '!' circle, and sometimes brings up a warning:
CAN'T PLAY
Summary: It might have bene moved, renamed, deleted, or removed from Zune Marketplace. If it's on an external hard drive, make sure the drive is connected and then try again.
ERROR CODE: C00D1197 (COOD1329)
Um, holy cr*p I think the Zune software destroyed my external HDD, it's not responding and not being recognized. If I lost all my data because of this software I'm going to be extremely pissed. I've never had problems with this hard drive, and I haven't even moved it in months. I didn't touch any of the connections anywhere on my computer. The only thing that has changed was that Zune Software has been running. Someone better have a good answer to what is going on. I can guess there was some disclaimer about using their software in the enduser agreement, but if it really did ruin my HDD I will find a way to sue the pants off of Microsoft, and this is coming from a whole hearted fan of Microsoft and someone who has been waiting day in and day out for today. Wow, I am so disappointed.
Excited to absolutely pissed of in a few hours, great job MS.