Please refer the below discussion.
Also, Check the Read & Write Permission to the following folders.
Let us know if that helps.
Thanks for your message. I doubt it would be a permissions problem as it works fine on one of the catalogs but not the other. Have checked the Read/Write permissions previously and they are fine.
Could it be a corrupted catalog causing the issue?
Please try and run the Integrity test on the Lightroom Catalog.
Open the Lightroom Option Or Alt key and select the Catalog to open and check the Option for Run the Integrity test.
Also, refer the below discussion
Tried above and it ran the integrity test then opened Lightroom. Didn't advise of any results to the integrity test. So assume that integrity is OK. As mentioned in my first message, an integrity test was done at time of backing up the catalog so was pretty adamant that this was not the problem.
Any other suggestions.