Apple Logo Stuck While Booting (Macbook Pro 15 (Late 2007)

I installed some RAM and added installation into my External Hardrive. I took out my external hardrive and I put it inside the macbook. So I turn it on and it comes with a apple logo. Few seconds, the circle is spinning. The last I had problem with it is that the circle in the bottom freezes out of no were. So since install a program on the external hardrive, now it shows a appe logo with the circle spinning. It been for 20 minutes doing that with out proceeding to the next step.



I am not sure if I should do the trick but I just know that it wont work correctly.

I tried all the tricks and it is not helping.



Please help and answer ASAP because I want this to WORK PERFECTLY !!!



Thank you,
Corrupted

Boot holding down CMD+V.

What does the last line say?

Sandbox: sandboxd(92) deny distributed-notifcation-post .

I'm not sure if thats the last line but thats the last line that is showing

Then it hears the "booting song" but not showing

Do a safe boot while holding in shift while booting.

Lion sandboxes applications, in the event they could cause harm.

Any application that runs while logged in can potentially cause problems. To avoid this, Apple had taken to the sandbox approach so that system damage does not occur.

Sounds like there may be a process trying to load at start up, possibly a driver.

Safe boot only loads core OS X startup items. See if the system will boot using this method.

So you think i should install Snow Leopard ? instead of Lion?

Does Safe Boot work?

It comes up loading in the middle then it goes off , then the circle keep spinning, & then it freezes again.

Did you try booting to the Recovery partition yet and run Disk Utility verify and repair? Let us know what it says.

I did try booting the recovery partition but it does not show any disk utility on it. It just goes straight to the apple logo then to the spinning circle then it freezes.

If you have a viable backup of critical data, and you have reliable install media, install whichever OS you want. Lion is obviously the latest and greatest. Snow Leopard is certainly a stable OS and may provide more flexibility with legacy applications. However Lion and iCloud are here to stay and Apple's way of creating obsolescence.

If you can, wipe and install Lion or Snow Leopard. It's really up to you. Consultation beyond capability will cost you,...

Well I tried everything, nothing passes threw :/ . But I don't have any back up data but I can install any OS.

Ill try snow leopard to see what comes up.

If anyone can find the problem please help

http://www.youtube.com/watch?v=QkptLLX7MWw&feature=channel_video_title