transferred to new EHD, getting error message when trying to back up

[amelia151]

I copied my entire catalog to a new external hard drive.  When I opened lightroom again I located the images on the new drive and have been using it without issue.  Now I want to close the program and I am getting this error message

Lightroom was unable to back up the catalog named “Amelia's pictures 2017”.

I am selecting the folder where the catalog is located and the same message pops up again.  What did I do wrong?!

[JP Hess]

What is the designated destination for the backup? Is that destination available?

[amelia151]

I'm not sure what you mean. Originally it would back up to the first external hard drive but I have transferred everything to the new one. The old one is unplugged from the computer so I am trying to back it up to the new hard drive (which is the same one it is reading from now).

[JP Hess · Accepted solution]

Apparently the old backup destination isn't named the same as the new backup destination. So when Lightroom attempted to do the backup the destination location wasn't available. You may not agree, but I don't think it's a good idea to have the catalog backup on the same drive as the working catalog. If you have troubles with that drive in the future and lose your working catalog it's possible that the backup will be bad as well.