MacBook Air won't startup after install
I installed S. Leopard on my MacBook Air using Remote Disk. I think the install worked, but NOW the computer doesn't seem to want to start – it is stuck on the initial startup screen involving the Apple icon and the grey, 'rotating' ring. I've let it do that for hours, just in case something was really going on, but no luck so far.
A couple of additional notes: once I started the install, everything seemed to be going fine, but at some point, I returned, and the computer was back at the login page. I assume that the install must have completed. I logged in and the desktop wallpaper had changed. Next, I checked the About this Mac window and it said '10.5.7'. I thought that was certainly odd, and I checked to see if there were any software updates. There were, and I told it to install them. It did, and then asked me to restart, which brings me to the current state of affairs.
So... what is going on? Did the S. Leopard install somehow do a partial installation and then blow up, leaving the disk half 10.5 and half 10.6? Is the computer REALLY doing something that will require hours or days on the first startup? Finally, is there any way to run any tests on it when it wont even get past the initial, Apple-&-spinning-wheel startup screen?
Thanks for any thoughts!
MacBook Pro, MacBook Air, Mac mini, Mac OS X (10.6), 2 GB memory