My Mac Pro (2009) is experiencing a bunch of problems lately. I'm not sure if they're related but it seems likely, so I'll start from the beginning and hopefully someone here can solve the mystery.
- after being shut down for a week while I was away, the Mac Pro fans went crazy on start-up. I force-restarted and the same thing happened so then I shut down and reset the SMC by unplugging the power cord. Restarted and fans returned to normal.
- then discovered ethernet is no longer working. According to the network preference panel I have no ethernet connected - the option isn't even there. Ethernet works fine when I test it on a MacBook from the same outlet and with the same ethernet cable..
- I then switched to wi-fi
- launched itunes and it gives me a -50 error (which is apparently network-related), then when I try to sync my iPhone it tells me my computer is no longer authorised and I have to delete all of my apps to continue with sync. When I try to authorise the computer, I get the -50 error again. Unfortunately the apps are the first thing itunes tries to sync, so I've been unable to sync my phone at all.
- a couple of days later I get the alert (paraphrasing) "There is already a [computer name]'s Mac Pro on the network. The name of this computer has now been changed to [computer name]'s Mac Pro (2)".
- itunes 11 is released so I update but errors persist
- more days later, and I get a new alert There is already a [computer name]'s Mac Pro (2) on the network. The name of this computer has now been changed to [computer name]'s Mac Pro (3)".
I've reset the PMU, and repaired permissions. I haven't been able to successfully run a hardware test with Mountain Lion on this computer.
Any help would be greatly appreciated!