Recently I had to reformat my HD, and reinstall the OS X and everything else. Computer is a Mac Pro (2010); OS X is El Capitan. After opening Lightroom (I have both the Cloud version and the standalone LR5, and the problem occurs with both), clicking on File, Open Catalog, locating a folder where all of my catalogs are stored on a different drive, and trying to open a catalog, I get a message saying the LR has to relaunch to use the catalog selected. After LR relaunches I get an error message: "The Lightroom catalog cannot be used because the parent folder “/Volumes/Master/Lightroom Cat/Cat-Hawaii” does not allow files to be created within it. Please either fix the folder permissions before continuing or choose a different catalog."
I have no clue what is meant by folder permissions requiring a "fix," so dozens of catalogs I've created over time are no longer available.
Has anyone a suggestion what I must do to salvage my existing catalogs?
Please provide full access permission to the Master folder in Volumes (/Volumes/Master).
Refer this link to provide permission : OS X Yosemite: Set permissions for items on your Mac
Let me know if this helps.