Yosemite need serious help!

[pankig]

Hello, I just recently upgraded from 10.6.8 to Yosemite and I noticed my computer was acting really slow with lots of internet and performance issues and I googled some questions and saw on the Apple forums to remove or replace files in my users/system/launch daemon folder. I did that but now when I boot my computer, after I put my password in, my screen is completely black, I can see my mouse but nothing else and I can't do anything. I tried re booting in safe mode but the same thing happened. I need my files...is there any way I can fix this as I did not make a backup. How would I at least re install Mac OS x and keep some of my files? Thanks

 

[tvguy]

I would reinstall 10.10 and see what happens. It should load all new file for the operating system. You will need to boot off of a thumb drive with 10.10. installer on it.

I hope you made a bootable drive... if not you will have to use another Mac to make one.

 

[pankig]

So I did command r in the beginning and re installed Yosemite through the boot loader....but the same thing happens after I login , a black screen of death.

 

[pankig]

I've backed up my files but have no idea how to 're install Mac...do I have to go to the Apple store and purchase a CD to 're install?

 

[dhlizard]

I would use a friend's computer to re download Yosemite, make a bootable thumb drive as previously advised.
Use Disk Utility to erase your HD, then do a clean install of Yosemite.

Be aware Yosemite can take several hours too optimize itself, during which computer speed is affected.

 

[SulaimanK]

I would rather advise you to try the fresh installation which wipes out all old and incompatible systems from the computer, Unless if you take full backup of your Snow Leopard you're good to go otherwise you may need to struggle with the slowness.

Furthermore before attempting this clean installation step, You should try to do partition installation and see whether you're occurring this slowness. If all goes stable then you can completely wipe out your main partition and then install the OS X Yosemite from the Bootable USB.

I guess i have been affected apart of this similar case long time ago with OS X Mountain Lion which i upgraded from Snow Leopard directly Mountain Lion and i have strongly been affected by the slowness of system, But the Apple Technician advised to try the clean installation instead which really helped me to solve this case much quicker than i expected!

 

[Weaselboy]

So I did command r in the beginning and re installed Yosemite through the boot loader....but the same thing happens after I login , a black screen of death.

Try a safe mode boot by holding the shift key just after the chime. That bypasses an login or startup items that might be causing a conflict. If it works in safe mode, that tells you a login or startup item is causing the problem.

Use the utility Etrecheck to find login/startup items.

Anything you messed up by deleting things in that daemon folder should have been fixed by the reinstall. Did the reinstall seem to complete okay?