I backed up my LR5 catalogue to an external hard drive. I tried launching LR from the ED and received the following message - LR cannot open the catalog named "LR 5 Catalogue" located on volume "Seagate Backup Plus Drive" because LR cannot save changes to this location.
copy your catalog to a local directory, or change your read-write permissions on the external drive if you want to keep that catalog on an external drive.
Thanks so much for the information. I did initially try to drag and drop
the backup of the catalog to LR5 which I had installed on the mac. I got
the same error message. I erased and partitioned another external hard
drive and then dragged the back up catalog from the external drive to it. I
then did what you advised copying the catalog from the reformatted drive to
the mac. LR came up and I was then able to reconnect with the missing
folders on the first external drive.
Thanks, again, for your help!