Black boot screen

[Treykwondo]

So , awhile back when i originally installed yosemite , I let a friend of mine borrow my mac for his presentation.. Well when i got it back , he had run some code to use a black boot screen.. Which really pissed me off , he tried to say " man its cool , you'll love it after awhile " and i told him i hate it , i want it back to the original. Well , he didn't know how to undo it.. And i have since banished him to exile island.... I spent forever trying to fix it , and i couldn't. I just formatted and reinstalled Yosemite thinking that it would fix it.. But it didn't. Could you guys help me out?

Its the dark boot screen with the apple logo , and the loading bar below it. I have an A1398 RMBP. Thanks in advance guys..

I have searched for a long time , the things i cam across either didn't work , or didn't apply to what i needed.

 

[Treykwondo]

Sadly still haven't found a fix to undo this. Please help.

 

[pigoo3]

Try the ideas (three) in the link:

A Solution for MacBook Pro Booting to a Black Screen | OSXDaily

Hopefully one of them helps.

- Nick

 

[harryb2448]

Reinforces the golden rule ~ never lend your spouse, money, motor car or computer.

 

[pigoo3]

Sounds like an excellent rule Harry!

- Nick

 

[Treykwondo]

OK!!! After finally starting to loath this... He changed it to the dark boot efi thing... And well.. I dont think theres a backup of the original. I want the original back... Does anyone know how to fix this without the original?