Yesterday I decided to apply the 10.5.2 update via Software Update. It downloaded and installed just fine, then proceeded to reboot my machine so I walked away to do something else. When I came back about about 10 minutes later, I was greeted by a blue screen with a black cursor. So I thought i’d wait some more. 30 minutes later and still nothing more than the same blue screen. Ok no problem, this happened to me on the Tiger to Leopard upgrade I thought, i’ll just reboot and be on my merry way. It worked for the upgrade, surely it would work now. So I reboot. Apple logo, grey screen, spinning circle. It kept doing that. Something’s wrong. Ok i’ll boot into Safe mode. Same thing. Upon booting into Verbose mode, there was some error about mDNSresponder which kept looping and looping.
Crap!
I knew my data was probably intact, but something had messed up the boot process during the upgrade.
It took the Leopard DVD and an Archive and Install to recover the system, but it recovered well with no loss of data and all my user information and applications intact.
So while the upgrade didn’t go smoothly, I got there in the end. If this happens to you, it’s not the end of the world. Just reinstall.