MacBook Air has suddenly become very slow at booting and shutdown I have a Late 2010 MacBook Air, and it has a 256 GB SSD, 2.13 GHz processor, and 4 GB RAM. It has been lightning fast ever since I bought it and I upgraded to OS X Lion and it was super fast. Boot time was 10-12 seconds (time to get to login screen), shut down time was 3 seconds.

During the last couple of months, my MacBook Air seems to be have slowed down regarding boot time and shut down time. Current boot time is 50-60 seconds, and shutdown time is 10-15 seconds.

I do not know the reason for this. Applications don't seem to have much lag though. It is my boot time that is a MAJOR problem!

I recently cleared a lot of useless memory on my computer and emptied the trash, and cleared the cache memory (with an app), and computer has a LOT of free space and no applications are loaded on start-up either. 

Can anyone tell me how to get back the original boot time performance?
Issue: After entering the password the computer would appear to freeze and become unresponsive. After about 20 mins it would eventually log in. User was claiming that browsing the internet was very slow and he could only access one page at a time.

Resolution: I had unbound the mac from the Active Directory domain and it fixed the issue. As it turns out the computer name had been removed from the AD Computers list.