Restoring Mail after a crash

My mac Pro crashed but on reboot everything is back except Mail. When I attempt to open the program I am told that it is necessary to first upload my emails and Mail folders. Once that's done I attempt to use Mail but it immediately freezes (spinning wheel of death that never resolves). I tried it 3 times and then replaced the Mail application from my Time Machine backup but it's still doing the same thing. I'm running Snow Leopard (for Final Cut reasons).