Permissions are Powerful

I arrived in the office this morning around 8:30, and Rob must have seen me drive in. My phone was ringing as soon as I went in the door—all of his preferences had reverted to defaults, so his Mail folders and rules were gone, his iChat accounts had to be re-entered, his keychains were toast, and some of his programs needed to be re-registered.

Rob is a very organized guy, and has his own methods of keeping information easily accessible. Needless to say, this was a blow to his productivity. After fiddling around for a while and manually re-entering mail servers and iChat configurations, it dawned on me that his Preferences folder at ~/Library/Preferences might have some permissions issues.

I’d normally recommend just going back a day or two in Time Machine to restore this folder to a known-good state, but Rob hasn’t backed up his machine in months. I examined the permissions on this folder, and found they were awry.

You can check the permissions of any file or folder on your Mac by clicking once on the item in question and selecting Get Info from the File menu; you can also right-click on the item and select Get Info from the contextual menu that appears. Sure enough, somehow he had no access to this folder, so Applications could not call on the individual preference files to display options correctly.

This wasn’t too surprising, especially since none of the changes we were making actually stuck after re-launching applications. By changing the topmost item in the Sharing and Permissions part of the Get Info window to Read & Write, applications were once again able to access their preferences.

Rob is updating his backup as we speak. You should, too.