If you have multiple catalog files and you used multiple versions of LR on your Mac then as you installed the newer versions of LR they took the older catalog file, made a copy of it and converted that copy to one that works with the newer versions of LR. This will happen again when you install LR CC and open it for the first time. So you will end up with another LR catalog file.
Just make sure it converts the most recent LR 4 catalog file.
You can't access those older catalog files without having LR then convert them to a format that works with the newer version of LR. In fact it is a bad idea to even try accessing them unless you have the older version of LR installed on your system.
Under the File menu item there will be a list of catalogs LR has open in the past. It is under Open Recent.
Thank you. That sounds quite logical but when I back up LR 4 it always back up to the Lightroom 3 Catalog 2-2.lrcat. So I don't know what is on the LR 4 catalogue or how to view it. I notice that in Preferences the default catalog is "most recent" so maybe that is the reson it is not backing up to or loading LR 4 catalog.
What do you mean it backs up to LR 3 catalog.
If you have LR 4 installed and you have a LR 4 catalog then the backups should be named after the LR 4 catalog.
Please show a screen shot of your File Manager window with the catalog and backup folder showing.
If you go to the File menu item and look in Open Recent it should list the catalog name LR is currently accessing. What is the name?
I appreciate your help Just Shoot Me but if you are still there could you please let me know if would be safe to open the Lightroom 4 catalog and then go back to the LR 3 catalog? Also if i need to put the LR catalog onto an external drive is it just a matter of copy and paste and then open it op on the other device connected to the external drive? Thank you again.
Yes you can open any that are listed then go back to the other.
I don't recall if LR needed to update a LR 3 catalog to a LR 4 catalog for it to work correctly. It's been a while since I used either LR 3 or 4. IIRC LR 5 needed to update a LR 4 catalog to work correctly with LR 5 and LR 6/CC does the same thing, updates an older catalog to work correctly with LR 6/CC.
You are currently using a LR 3 catalog. Go to the Help menu and select about LR to see exactly which version of LR you have open.