Message 188011 - Python tracker

I am installing Python 3.31 on a Mac running OS 10.8.2 and have already installed ActiveTCL 8.5.13. When I try and launch IDLE, the icon appears on the dock for a second and then disappears and the application doesn't run. I have already installed both Python and Active TCL in the same way on two other Macs and it has run just fine, so I don't know why it's not running on this one. Is there anything specific that would cause this to happen?

Thanks,
Ben