Security Agent blocking startup

I'm using a mid-2012 2.9GHz 13" MacBook Pro with a replaced battery, hard drive, and SATA cable.

Every time I try to boot up the laptop, the screen goes black when the progress bar reaches about halfway, and an Invalid Caller popup appears saying that only Apple software and run the Security Agent. I'm unable to click on it, so I have to shut down the laptop again.

If I try to boot in safe mode, the progress bar makes it about three quarters of the way across the screen, but then some diagnostics appear in the top left corner of the screen, and the boot process starts again.

Recovery mode will start up, and running first aid on the hard drive and the partition works fine, however it has failed while running on the hard drive occasionally.

I've booted in single user mode, and tried run fsck -fy, and the first time it said that files had been modified. All of the subsequent times, it's run without issue, but exiting single user mode by typing reboot, or sometimes even waiting long enough will cause an error where "pci pause: SDXC" appears on the command prompt and then it freezes.

I've tried a PRAM reset and it didn't work.

I don't think I'm running the latest version of OS X (I haven't updated the laptop in the past few weeks, but if there hasn't been an update since about Christmas, I'm fine) and without being able to boot into it, I won't be able to.

Thank you for the help!

MacBook Pro, OS X El Capitan (10.11.2)

Posted on Mar 19, 2016 7:27 AM

Reply
3 replies

Mar 19, 2016 11:03 AM in response to BaronPaprika

Usually those messages indicate a hardware fault in the storage subsystem, such as a failed SATA cable, but you can try the following.

Please restart the computer in safe mode. Certain caches maintained by the system will be rebuilt.

Safe mode is much slower to start up than normal. The next normal startup may also be somewhat slow.

If you do not use FileVault 2 in OS X 10.7 ("Lion") or later, then you can restart as usual (not in safe mode) when the login screen appears. There's no need to log in while in safe mode.

If you do use FileVault 2 in OS X 10.11 ("El Capitan") or later, or if you're not sure whether you use it, log in as usual while in safe mode, then restart (not in safe mode.)

If you use FileVault 2 in OS X 10.9 ("Yosemite") or earlier, or if a firmware password is set, or if the startup volume is a software RAID, you can’t start in safe mode. In that case, ask for other instructions.

Mar 19, 2016 1:48 PM in response to BaronPaprika

The startup drive is failing, or there is some other internal hardware fault.

Back up all data on the drive immediately if you don't already have a current backup. There are ways to back up a computer that isn't fully functional—ask if you need guidance.

Make a "Genius" appointment at an Apple Store, or go to another authorized service provider.

If privacy is a concern, erase the data partition(s) with the option to write zeros* (do this only if you have at least two complete, independent backups, and you know how to restore to an empty drive from any of them.) Don’t erase the recovery partition, if present.

Keeping your confidential data secure during hardware repair

Apple also recommends that you deauthorize a device in the iTunes Store before having it serviced.

*An SSD doesn't need to be zeroed.

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

Security Agent blocking startup

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.