Previously owned MacBook pro retina security

UPDATE: Issue resolved, please delete, and thank you for all your help!

You can basically prevent this by ensuring the user's iCloud account isn't signed into the Mac in System Preferences. However, to be extra sure, I recommend reformatting the system so you get a clean slate.

See: http://www.mac-forums.com/apple-notebooks/333698-reset-macbookpro-factory-settings.html

Following that, here is a selection of security tips:

http://www.mac-forums.com/security-awareness/333699-lockdown-thermonuclear-security.html?highlight=

Hope that helps!

The icloud is signed out. It's been formatted but from research I saw someone say the only way to stop that from happening is reset the pram? I just want to know if after all of that it's safe

No the PRAM would not make much of a difference. This is closely tied to Apple's cloud security architecture. If you have now linked the device to your own iCloud account, you are safe.

So 100 percent if I sign in to my I cloud the previous owner cannot wipe or lock my machine through find my mac?

You say it has been reformatted, therefore I assume you have a clean install of OS X. Then it's 100% safe.

If you want to be extra safe, I researched a bit and yes the PRAM may have some traces left as Apple uses it to lock the device remotely. But, if you set up FMM with your own iCloud account, you are 100% safe and don't need to reset PRAM: https://apple.stackexchange.com/que...ock-erase-my-second-hand-mac-with-find-my-mac

So the be 110% safe:
- Reformat the drive
- Reset PRAM
- Setup FMM with your own Apple ID
- Make the previous owner go to iCloud.com and verify removal of the Mac from his FMM

For future reference, there's also this:
https://support.apple.com/en-us/HT201065

Congratulations, yogi, on breaking through the 2000 posts.

Ian

Suggest you get an Apple ID and download El Capitan and burn it to a USB thumb drive using DiskMakerX. The boot from the thumb drive, erase the hard drive if you are ultra cautious use the seven pass method but leave it overnight, install OS X.11 El Capitan and set it up with your user name, passwords, network settings etc. and update to OS X.11.4.