When I initially launched Pandora on my Nook Color I entered my Pandora account name and password and since then I get the message
""Error Unable to playmusic [sic] at thos time, please try again" with only an "exit" button
My Wifi connection appears to be live at the time as I had just surfed the web, visited the store, etc.
Theres a strong possibility thats it's due to PANDORA's server.
As long as you are able to access other website's and your wifi is up and running on your nookcolor... then it's not a device issue, but a PANDORA server issue.
I think you need to call pandora for that.