Macbook pro freezes on startup

My macbook pro osx10.7 has started to freeze when i try to restart. I think it started when i upgraded to Lion. After clicking on 'restart', the machine shuts off, restarts normally, goes to the gray screen with the apple logo, then goes to a black screen and freezes there. I have to power off, and start with the power button. The machine then starts normally. I have tried repairing disk permissions, about the extent of my expertise. Help please?

Let's check the hard drive first:

Boot your machine by holding down the Command key and the R key as soon as you hear the chime (bong). That will boot your machine to the Recovery partition in Lion. Once there, select Disk Utility and verify the hard drive. Let's see what it says. Post back the results.

It says the drive seems to be ok.

OK, that's good. Next, let's check the memory on your machine:

Download the free MemTest for Mac from here. (And pay no attention to the "MacKeeper Ads" on that site.) Run the extended tests on your MacBook Pro.

Let us know the results of the tests.

All tests ok....

Freezing is usually caused by a hardware fault. MemTest does a very comprehensive test of the memory so I'm fairly certain the trouble is not there. Unfortunately, Disk Utility does not always have the ability to find hardware problems with the hard drive. The verify check does a file and folder integrity scan and can sometimes respond to a bad block.

I hate to have you run one more check, however, I think it might be a good idea to do so. The S.M.A.R.T. utility can discover problems with the hard drive that Disk Utility can't. Download the utility from here and run it.

If the hard drive passes that test, it means that there is an intermittent problem causing the freezing. The next step would be to try booting in Safe mode to see if the freezing occurs there. Booting to safe mode is easy - hold down the shift key as soon as you hear the boot chime.

The hard drive passed all tests. I booted to Safe mode, and the problem persists; bong, grey screen with apple logo, black screen and freeze....

chscag's advice seems to have ruled out the things I was thought were possible causes. Have you tried installing the combo updater for whichever Lion version you're running? Apple - Support - Downloads

That seems to have fixed a few minor issues for me that had mysteriously cropped up all of a sudden.

Thank you Slydude, the combo updater seems to have fixed the problem. And thanks to chscag for his help and for introducing me to ways to troubleshoot my mac.

Glad that has worked for you. It seems to have fixed my issues with screen sharing in Lion which had been working fine until a few days ago.

mlhope said:

Thank you Slydude, the combo updater seems to have fixed the problem. And thanks to chscag for his help and for introducing me to ways to troubleshoot my mac.

Click to expand...

Thanks for posting back and letting us know. My good friend from LA beat me to it about installing the combo update. (That's why he's making the big bucks)
;P

Glad it worked out for you. Have fun and visit us often.

chscag said:

Thanks for posting back and letting us know. My good friend from LA beat me to it about installing the combo update. (That's why he's making the big bucks)
;P

Click to expand...

Those checks seem to have gotten lost in the mail. You wouldn't know anything about that would you? : I sense the involvement of a certain Canadian gent.