and do it quickly.
First create a new Admin account on that machine and restart it as normal.
Can you log into the new Admin account?
If no,
Find either the disks that came with it or a copy of OS X retail installation disk.
Boot from the disk and follow the instructions to do an Archive and Install. (it should be the default method)
Now does it work?
If no,
Time to consider a re-format of the drive and install of OS X again.
what version of OS X do you have?
P
Hi, I've been working for 2 weeks in Safe Boot cause my Mac Pro won't start up and load up as normal. It's as if something is blocking it. I've reloaded my Snow Leopard 10.6.3 and tried to get going but at one point the screen said the operating system was not compatible with this version. It worked well before. Thanks.

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