I downloaded Lightroom 6 CC for analysis but I want to continue using Lightroom 4. I am now unable to backup my catalog on Lightroom 4. There is a CATALOG.lrcat.lock file in the CATALOG directory. If I remove that file can I continue using and backup Lightroom 4? Is there is a better way continue using Lightroom 4?
Yes, you should delete the .LOCK file.
When Lightroom shuts down normally that lock file is automatically deleted. Sometimes Lightroom doesn't shut down normally and that file gets left behind. The only way you will be able to get back into Lightroom is to delete the lock file. So, yes, you can delete it with confidence.
Thanks for your quick response. I renamed it just in case and tried to exit with backup and it seems to have completed as usual. Thank you also Jim.