Make sure all copies of Photoshop CS6 on all your Macs have been in fact updated to Photoshop 13.0.6.
Have you tried Purging the Cache through the Tools menu in Bridge for all offending folder(s)?
Have you Repaired Permissions with Apple's Disk Utility?
The copy that doesn't work is 13.0.6. My wife is using the other machine, but its copy must be too because I installed it last week. All folders were offending, so I purged the entire cache. Yes I repaired permissions on the machine with the problem recently, but I'm doing so again as I write this. There were only two lines of repair, both on Safari.