Sudden hang & Macbook won't boot anymore

Hi, as my info reports i own a 2010 MacBook Pro 13" with Mac OS X 10.6.6; today i ran some updates (itunes, safari and a third i can't remember), everything went nice and the mac was powered by plug.
Just after the reboot everything worked nicely and i used it for an hour or so; when i came back to my mac two hours later, i tried to start Skype but it sid "Unable to create a lock file"... i then tried to reboot or shut it down, but it didn't respond; i tried to open Safari, and it then completely hanged, so i had to shut it down keeping the power button pressed.
At reboot there was as usual the Apple in the middle of the green screen with the swirling pattern, and a gray bar loading REALLY slowly (it took 10 minutes); when the bar ended, the mac shat down.
I powered it up again and there was the bar again, this time it was a little bit quicker and after 4 minutes or so the bar ended and there was only the usual swirling pattern, but after 20 minutes the macbook did not move from the gray screen.
Now if i try to start it, it just hangs on the gray screen with Apple and swirling circle.
I tried to clean the NVRAM, to boot in Safe Mode (after 20 minutes nothing happens so i gave up), i booted in Verbose Mode but it just hangs without saying anything useful; it does boot in Single User Mode, but fsck says the file system is OK.
I started from the Install CD and in Disk Utility Repair Permissions is grayed out, and it says "Owners Enabled: NO" below; Verify and Repair Disk just say the disk is OK.
I'm glad for any help!

I had to do first an Archive and Install, this fixed the boot.
Then i saved all my data and did a complete format.
Now everything is working fine and i lost really little.
However, the problem was indeed the deactivation of Permissions on my boot disk.
Is there any other way to fix this in the event this could happen again? Thanks!

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Checking filesystem on /dev/pixie/btrfs
UUID: e04cc661-e31a-4dbf-870d-664bc913e34a
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[ 240.335542] Not tainted 3.19.2-1-ARCH #1
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[ 240.340263] mount D ffff8800cf2837f8 0 539 453 0x00000000
[ 240.340277] ffff8800cf2837f8 ffff8800cf2331b0 0000000000013f00 ffff8800cf283fd8
[ 240.340286] 0000000000013f00 ffffffff81818540 ffff8800cf2331b0 ffff8802094f67a8
[ 240.340291] 0000000000000004 ffff8800cf283758 ffffffffa0a2fc91 ffff8802094f67a8
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[ 240.340335] [<ffffffffa0a2fc91>] ? set_extent_buffer_dirty+0x71/0xc0 [btrfs]
[ 240.340357] [<ffffffffa0a05796>] ? btrfs_buffer_uptodate+0x56/0x80 [btrfs]
[ 240.340366] [<ffffffff8155e999>] schedule+0x29/0x70
[ 240.340389] [<ffffffffa0a47745>] btrfs_tree_lock+0x65/0x200 [btrfs]
[ 240.340396] [<ffffffff810b4380>] ? wait_woken+0x90/0x90
[ 240.340410] [<ffffffffa09e5cd9>] btrfs_search_slot+0x799/0xaa0 [btrfs]
[ 240.340425] [<ffffffffa09e79f5>] btrfs_insert_empty_items+0x75/0xd0 [btrfs]
[ 240.340446] [<ffffffffa0a47a37>] btrfs_insert_orphan_item+0x67/0xa0 [btrfs]
[ 240.340465] [<ffffffffa0a4a12e>] insert_orphan_item+0x5e/0x90 [btrfs]
[ 240.340482] [<ffffffffa0a4c531>] replay_one_buffer+0x361/0x380 [btrfs]
[ 240.340504] [<ffffffffa0a2f244>] ? alloc_extent_buffer+0x34/0x370 [btrfs]
[ 240.340523] [<ffffffffa0a488f3>] walk_down_log_tree+0x1d3/0x410 [btrfs]
[ 240.340540] [<ffffffffa0a48bfb>] walk_log_tree+0xcb/0x1d0 [btrfs]
[ 240.340558] [<ffffffffa0a507f7>] btrfs_recover_log_trees+0x1e7/0x490 [btrfs]
[ 240.340575] [<ffffffffa0a4c1d0>] ? replay_one_dir_item+0xf0/0xf0 [btrfs]
[ 240.340596] [<ffffffffa0a08b3e>] open_ctree+0x17ae/0x2030 [btrfs]
[ 240.340609] [<ffffffffa09dd633>] btrfs_mount+0x843/0x920 [btrfs]
[ 240.340618] [<ffffffff8117b7aa>] ? pcpu_alloc+0x35a/0x680
[ 240.340628] [<ffffffff811d5d68>] mount_fs+0x38/0x1c0
[ 240.340634] [<ffffffff8117bb05>] ? __alloc_percpu+0x15/0x20
[ 240.340641] [<ffffffff811f116b>] vfs_kern_mount+0x6b/0x120
[ 240.340647] [<ffffffff811f4184>] do_mount+0x224/0xb40
[ 240.340653] [<ffffffff811f4dae>] SyS_mount+0x7e/0xe0
[ 240.340661] [<ffffffff81562809>] system_call_fastpath+0x12/0x17
[ 240.340671] INFO: task btrfs-transacti:561 blocked for more than 120 seconds.
[ 240.342927] Not tainted 3.19.2-1-ARCH #1
[ 240.345175] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 240.348473] btrfs-transacti D ffff88020b88bd98 0 561 2 0x00000000
[ 240.348483] ffff88020b88bd98 ffff880211edc590 0000000000013f00 ffff88020b88bfd8
[ 240.348491] 0000000000013f00 ffff8802162289f0 ffff880211edc590 ffff8802094a70c8
[ 240.348496] ffff8802094d8000 ffff880200000000 ffff8802094d8000 ffff880200000033
[ 240.348501] Call Trace:
[ 240.348511] [<ffffffff811b5d1a>] ? kmem_cache_alloc+0x16a/0x180
[ 240.348525] [<ffffffffa09e07ca>] ? btrfs_free_path+0x2a/0x40 [btrfs]
[ 240.348543] [<ffffffffa0a64213>] ? __btrfs_run_delayed_items+0xf3/0x1d0 [btrfs]
[ 240.348550] [<ffffffff8155e999>] schedule+0x29/0x70
[ 240.348568] [<ffffffffa0a0b555>] btrfs_commit_transaction+0x2a5/0xbe0 [btrfs]
[ 240.348573] [<ffffffff810b4380>] ? wait_woken+0x90/0x90
[ 240.348590] [<ffffffffa0a06fc5>] transaction_kthread+0x1d5/0x240 [btrfs]
[ 240.348605] [<ffffffffa0a06df0>] ? btrfs_cleanup_transaction+0x5a0/0x5a0 [btrfs]
[ 240.348611] [<ffffffff81091748>] kthread+0xd8/0xf0
[ 240.348617] [<ffffffff81091670>] ? kthread_create_on_node+0x1c0/0x1c0
[ 240.348624] [<ffffffff81562758>] ret_from_fork+0x58/0x90
[ 240.348629] [<ffffffff81091670>] ? kthread_create_on_node+0x1c0/0x1c0
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Won't boot anymore but in safe mode

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Reinstall OS X without erasing the drive
Do the following:
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http://discussions.apple.com/message.jspa?messageID=4112865
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<When iPod is plugged in at startup, the MacBook does not startup; unplugging iPod lets it startup.
yes, it seems that the kernel is not loading
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My Macbook won't boot up because there sin't enough free space to run the startup disk. My Macbook now won't go past the blue screen so exactly how am I meant to be able to delete files if I can't access the computer?

Do you have a bootable backup?
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If you have OS X 10.7 Lion or 10.8 Mountain Lion, you don't have many choices in recovery mode (boot holding the command and r keys down).
If you have a FireWire or Thunderbolt connection, you can try target disk mode with another mac.
If none of those work, perhaps your local Apple store can help with a bootable external drive.

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Hi all,
Past week i've bought a second hand PM G5. At first it seems to be all ok, but right now its not working anymore.
I've managed to install the OSX on the first evening i've had the PM G5. After installing evrything seemed to be fine. But after 30 minutes surfing on the internet, it froze. I had to give it an hard reset by holding down the power button.
After turning it of, it won't boot anymore. after a few times trying with 10 secconds between it, i unpluged the powercabel for 2 minutes. Wile turning it on after 2 minutes, it was booting , but it stopped booting after 1,5 minute and froze.. after hard resetting it, i've managed to boot it right. The OS seemed to be ok again, but after 5 till 10 minutes it froze again.
Right now it won't boot anymore... it starts (without the front light, this light only blinks fast once i turn it on, but after that no more. Sometimes it won''t even flash.
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The i've replaced the memory with 4 kind of difrent pairs, but won't do a thing either. At last i replaced the Logic Board, this won't even do a thing about it.
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I've tested it in AHT, but evrything was working well, according to AHT. I've managed to get the system log, but nothing scarry though here also, only some 122 errors some times. (download the system log here: http://www.mijnbestand.nl/Bestand-F4DDN66WLRCI.log )
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What can i do next to get this thing work?? I'm getting nut's here..
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MArtijn Snoek

Hi martijnsnoek, and a warm welcome to the forums!
Can you count the beeps or flashes?
1 beep = no RAM installed
2 beeps = incompatible RAM types
3 beeps = no good banks
4 beeps = no good boot images in the boot ROM (and/or bad sys config block)
5 beeps = processor is not usable
In addition to the beeps, on some computers the power LED will flash a corresponding number of times plus one. The LED will repeat the sequence after approximately a 5-second pause. The tones are only played once.
Note: In this case, a flash is considered to be 1/4 second or 250 ms or greater in length.
http://support.apple.com/kb/HT1547
So, with the info you given, two things come to mind...
Bad solder joints around the RAM slots, try heating that area with a Hair Dryer for 3 to 5 minutes, then see if it starts.
If you can get it running, Get Temperature Monitor to see if it's heat related...
http://www.macupdate.com/info.php/id/12381/temperature-monitor
And/or iStat Pro...
http://www.islayer.com/apps/istatpro/
If you have any temps in the 70°C/160°F range, that's likely it.
BTW, have you blown the dust out of it since you got it?

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Have you tried booting into Lion recovery mode? Boot holding the command and R keys down.

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Sudden hang & Macbook won't boot anymore

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