, How do I get rid of "MRT"?

Possible Fixes for El Capitan or Later

[You should try each, one at a time, then test to see if the problem is fixed before going on to the next.]

Be sure to backup your files before proceeding if possible.

1. Resetting your Mac’s PRAM and NVRAM
2. Reset the System Management Controller (SMC)
3. Start the computer in Safe Mode, then restart normally. This is slower than a standard startup.
4. Repair the disk by booting the from the Recovery HD. Immediately after the chime hold down the Command and R keys until the Utility Menu appears. Choose Disk Utility and click on the Continue button. Select the indented (usually, Macintosh HD) volumeentry from the side list. Click on the First Aid button in the toolbar. Wait for the Done button to appear. Quit Disk Utility and returnto the Utility Menu. Restart the computer from the Apple Menu.
5. Create a New User Account Open Users & Groups preferences. Click on the lock icon and enter your Admin password when prompted. On the left under Current User click on the Add [+] button below Login Options. Setup a new Admin user account. Upon completion log out of your current account then log into the new account. If your problems cease, then consider switching to the new account and transferring your files to it - Transferring files from one User Account to another.
6. Install Combo Updater Download OS X El Capitan 10.11.6 Combo Update or Download macOS Sierra 10.12.5 Combo Update and install.
7. Reinstall OS X by booting from the Recovery HD using the Command and R keys. When the Utility Menu appears select Reinstall OS X then click on the Continue button.
8. Erase and Install OS X Restart the computer. Immediately after the chime hold down the CommandandRkeys until the Apple logo appears. When the Utility Menu appears:

1. Select Disk Utility from the Utility Menu and click on Continue button.
2. When Disk Utility loads select the drive (out-dented entry) from the Device list.
3. Click on the Erase icon in Disk Utility's toolbar. A panel will drop down.
4. Set the Format type to Mac OS Extended (Journaled.)
5. Click on the Apply button, then wait for the Done button to activate and click on it.
6. Quit Disk Utility and return to the Utility Menu.
7. Select Reinstall OS X and click on the Continue button.

Although Apple has pulled MRT v1.21 and replaced it with v1.20, it doesn't appear that it will replace the problem version.

Some users have found that running MalwareBytes will remove whatever MRT is having problems with, followed by a reboot.

Basics for Uninstalling Software

Most OS X applications are completely self-contained "packages" that can be uninstalled by simply dragging the application to the Trash. Applications may create preference files that are stored in the /Home/Library/Preferences/ folder. Although they do nothing once you delete the associated application, they do take up some disk space. If you want you can look for them at the above location and delete them, too.

Some applications may install an uninstaller program that can be used to remove the application. If you cannot find the uninstaller then you could download the freeware, Easy Find, to locate files that need to be removed. The places you need to search include:

1. /Home/Library/Applications Support/ folder. Check if the application has created a folder then delete the folder that's in the Applications Support folder.
2. Applications may install a startupitem or a LogIn item. Startupitems are usually installed in the /Library/StartupItems/ folder or the /Home/Library/StartupItems/ folder. LogIn Items are set in the Users & Groups preferences. Open it in System Preferences, then click on the LogIn Items tab. Select the item from the list and click on the Delete [-] button to remove it.
3. Some software use startup daemons or agents. Look for them in /Library/LaunchAgents/ and /Library/LaunchDaemons/ or in /Home/Library/LaunchAgents/.

Some applications install a receipt in the /Library/Receipts/ folder. Usually with the same name as the program or the developer. The item generally has a ".pkg" extension. Be sure you also delete this item as some programs use it to determine if it's already installed.

There are many utilities that can uninstall applications. Here is a selection:

1. AppZapper
2. AppDelete
3. Hazel
4. AppCleaner
5. CleanApp
6. iTrash
7. AppBolish
8. AppUninstaller
9. Uninstaller

For more information visit The XLab FAQs and read the FAQ on removing software.

Are you really running El Capitan? Only macOS 10.12 and above should have received that update.

MRT v1.20 has just been posted, replacing v1.21 which obviously has a problem. These updates only occur every 24 hours while your computer is awake, so it may take some time for this fix to make it to your computer.

I have the same problem since yesterday,

Any suggestion, as other persons I have tried to restart, delete (but even when I change permissions it doesn't work) ...
I am stuck, the only suggestion I saw right now is wait or uninstalling the entire OS ... which I don't really want.

I would be grateful for any remark 🙂

IEDGreek wrote:

What do you mean "it doesn't appear that it will replace the problem version"

Normally, older files will not replace newer ones when performing an update. Since v1.20 is about a month older than v1.21 was, users are reporting that they are still stuck with v1.21 after attempting to force an update. So only those who never updated to v1.21 will be prevented from having the problem.

Does Apple have a solution or not?

Apple has now posted an MRT version 1.22, which should be the solution for all.

DeCoverly wrote:

Having the same problem...how do I download version1.22?

It should install itself within 24 hours, as long as your computer is awake at the random time it uses to install such things.

If you can't wait that long, you can speed things up by copying and pasting the following command into a Terminal window. The Terminal app is in /Applications/Utilities/

sudo softwareupdate --background

You will be asked for your admin password. When you enter it nothing will be seen. Just hit enter after typing it.

The only feedback you get will be "Triggering background check with normal scan ..." and it may take up to five minutes before the background process completes. You can follow it's progress, if you want, by viewing your install.log in the Console application.

I too have this problem.. my hard drive is being filled as fast as my internet will allow, and I also cannot get into preferences, account/user etc.

AND it is SLOW!

If I boot in safe mode - I CAN get in to preferences, but as soon as I connect to internet - I can no longer access preferences control panels..

Has Apple created their own Virus ?

Followed your instructions and the MRT memory sucking problem is completely resolved! 😁 I followed the progress and it took considerably longer than 5 minutes for MRT to disappear from the Activity Monitor with simultaneous restoration of my iMac's memory. So, be patient for it to be completed. Thanks again!!!

Thanks MadMacs0.

Was hoping 1.22 would install overnight, but it didn't. I tried your fix in terminal but it doesn't seem to be working (or I did something wrong). It's been one hour and 20 minutes, and the MRT in activity monitor is still there and growing. Install.log doesn't show any activity after I typed the command into terminal...

I'm about out of ideas. Everybody else I've dealt with today eventually received the update.

You can check to see if the new version installed with a Terminal command. Triple-click the following to copy then entire line.

defaults read /System/Library/CoreServices/MRT.app/Contents/version CFBundleShortVersionString

If it's "1.22" then reboot and you should be good to go.

I tried the MalwareBytes this morning. It got rid of the MRT from Activity Monitor (as well as a couple of other things). I rebooted, but things were still running super slow. Left it for a couple hours, came back, and it was running normal again. So I don't know whether running the MalwareBytes scan fixed it or if 1.22 installed at some point. Upshot is I'm all set.

Thanks for your help MadMacs0! Appreciate the assistance...

Cheers.

Glad everything worked out.

Just to clarify one thing. The problem you had was actually cause by at least one of those "other things" that MalwareBytes found. The faulty MRT was struggling to remove it and apparently put itself in an endless loop due to a coding error. 1.22 seems to be a fully functional MRT, so hopefully it will help to keep you safe from most adware/malware going forward.

Hi there from Croatia!

I got the same problem for the first time on August 24th 2017. I was tried all solutions offered but nothing helps, or it does... you can not delete it, move it, unlock file to change privileges, nothing.

Well, first I downloaded some free trial Antivirus for Mac which found three critical files on my MBP (some Trojans), and deleted them. At first nothing happened. Than I allow MRT to work in background (it was the only option, it works all the time no matter if I quit it) to see how far it will go in eating my CPU and HD storage. This morning I wake up my MBP to check numbers, MRT came to 35 GB! OK, I quit them in Activity Monitor and...... he is gone, gone, all day I have not see MRT process again.

The same thing with font(something) process, the same scenario as MRT. I got reed of all double fonts and kills this process too.

I work on MacBook Pro, last Sierra version.

And one more thing, when I work in Safari or Chrome, my machine is now silent.... wonderful, I forget this sound of peace.