Hi Folks I am having this annoying problem for weeks now. 9/10 times, if i want to make an update on the mac app store, it crahes, (either during downloading or during installing) my macbook reboots. i am trying now to update itunes 11, no chance at all, it freezes during downloading. i repaired permissions and disk. well still same problem. strange is, (hence this was a time machine backup from another macbook pro, i have this problem on both computers. i reinstalled osx 100 of times, tried to use timemachine backup, or the migration assistant, created a new user just for the updates, still have the same problems. i am running osx 10.8.2. Main Computer is a Macbook Pro Retina (this is were my timemachine comes from) Crashes 9/10 times Second is a Macbook Pro 2010 (Crashes constantly) Third Macbook White in my office (Worked after several attemps) all 3 have same tm backups). can anybody please help me with this. is there a problem with my time machine backup i am using all the time? strange is, downloading osx mountain lion from the appstore is always working.