How to approve “Unapproved caller” whilst installing the software?

Question

I'm trying to install FUSE for OS X, but it fails with the message:

Unapproved caller.

SecurityAgent may only be invoked by Apple software.

How do I approve the caller or get rid of that error? What this error actually mean?

Answer 1

It seems it's some kind of temporary glitch, as it usually helps to restart the machine.

Other suggestions:

• Reboot into Safe Mode, then Verify and repair drive

  1. Reboot and hold the CMD+R keys
  2. Select Disk Utility
  3. Click on the image under my drive
  4. Verify and repair drive

• You may try to remove the cache files/folders located in /var/folders directory (not recommended) or move them into Trash.

  Normally cache files should be cleared every few days by Launch Daemon (/System/Library/LaunchDaemons/com.apple.bsd.dirhelper.plist).

  If the files can't be removed, reboot into Single Mode, run fsck, mount the root partition and run rm -vR -- /var/folders/*. Which is:

  1. Start on single user mode: Hit the CMD+S keys at start-up
  2. At the line, type (after root): fsck -fy and hit the Enter key.
  3. Mount the root drive by: mount -uw /
  4. Remove the cache files by: rm -Rf /var/folders/* (make sure you won't do any typo!).
  5. Reboot by typing: reboot.

Answer 2

I had this problem and tried many online suggestions. My situation was different, I had trashed the content of hidden var/folders/ after seeing a post that said it was all leftover junk from earlier flash updates. Turns out Mavericks needed something and was very unhappy and determined to teach me a lesson. Would not let me use TM to recover. I solved it by booting using computer #2, Target Mode and Onix (show hidden) so that I could copy the files out of computer #1 trash back to the hidden file.