Disk Utility not opening in Mavericks I had used a Seagate external HD as Time Machine back up for a year or so. Since I got a gift of a better EHD now I wanted to erase all data in the old EHD. I thought a simple Format through Disk Utility would be easy.

Recently I updated my MacBook Pro 15″ into Mavericks. Today when I tried to open Disk Utility, it did not open, with the following error:


  You can't use this version of the application "Disk Utility" with this version of OS X. You have "Disk Utility" 13.


Where shall I find Disk Utility suitable for Mavericks? Is there any other easy procedure to empty my EHD?
It appears that Disk Utility.app has been replaced by an incorrect version, or you are attempting to open a Disk Utility from a different installation of OS X. Make sure that you are opening Disk Utility from /Applications/Utilities and not from any other volume.

You can replace Disk Utility by re-installing OS X, which will replace all Apple apps in /Applications with new versions from the installation media.

Alternatively, you can use a Time Machine backup or other backup media to obtain a replacement copy of Disk Utility.

If you have a second computer with exactly the same version of OS X, you can copy it from that computer into the same location on the first computer. Once you have done this, boot into the Recovery HD with ⌘R and Repair Disk Permissions to ensure that the app has the proper permissions.