Messages will not login; just sits and spins Whenever I open Messages, enter my credentials, and attempt to login the status indicator spins forever and the application never authenticates me and loads.

I had this issue on Mavericks and still have it on Yosemite. I tried removing the frameworks for Messages/iMessage in OS X and even reinstalled the OS from the recovery partition, but nothing works.

Has anyone else had the same issue and any luck with resolving it? Thanks for your time!
My logic board was recently replaced in this Macbook and the vendor never serialized the newly installed logic board. I discovered this by going to "About This Mac" and seeing the serial number being reported as "Unknown".

The vendor corrected this actually applying a serial number to the logic board, which required specialized software that they had to boot off of from a DVD.

Once the serial number was applied then Messages worked just fine.