can't save preferences in PS CS5

[Fred16B7]

Just installed PS CS5 from disk.  When I try to save preferences or chamge workspace I get the message in pic below.  How do I fix? I've done what it says but to no avail.

 

[marliton]

Hi. Please try fixing the system permissions and reinstalling the application: https://helpx.adobe.com/x-productkb/global/repair-disk-permissions-running-disk.html

[Fred16B7]

No help Marlon.  Still getting the same message as earlier.  BYW, I'm running PS on a 2007 iMac upgraded to El Capitan.  Disk Utility says all is OK.  Any other options?

Thanks!

[Fred16B7]

Success!  Used Tinker Tool to show hidden files, found PS settings and deleted.  All working fine now!