Is this error important?
Q Should I be worried about the warning message that appeared when I used Disc Utility following an unexpected quit by Mail? It says ‘SUID file – System/ Library/ Core Services/ Remote Management/ ARDAgent.app/ Contents/ MacOS/ ARDAgent has been modified and will not be repaired’. I’m using a mid-2010 Macbook Pro with Mavericks. Disk Utility reports everything else as OK, verifying and repairing some permissions. I have tried to find the file in Library with no success. Andrew Knight
A Don’t worry this is perfectly normal. Disk Utility checks the permissions for the OS X system files against a master list that details the ‘correct’ permissions for each one. In 10.5, some of these files were shuffled around into different subfolders and this changed their effective permissions very slightly. Disk Utility wasn’t updated to account for this and so it throws up these erroneous warnings. Although this plays hell with the obsessive-compulsive part of my brain and sets off the tic in the corner of my eye, Apple has confirmed that this message is not a concern and should be ignored. See https://support.apple.com/en-gb/ HT203172 for a complete list of other Disk Utility warnings you can ignore.
Even if Repair Permissions shows warnings there isn’t necessarily anything wrong.