Please check the following link: "Failed to install" error received when installing Adobe Creative Cloud desktop app
Also make sure to update Lightroom to the latest version 6.7.
I tried re-installing - did not work. Then I downloaded CC cleaner and ran it. When re-installing, it indicated that there still were components and asked whether they should be replaced; I did. When trying to run program, it still shows "configuration error" and error 1. Something still was running, which i had to force-quit. The Adobe website to download CC programs only has offers to start a new subscription, but not a replacement for my one time purchase.
I would suggest you to uninstall Lightroom from your account.
Once done, enable Root account, log out from your account and login to the root account and install Lightroom in the root account.
Please check how to enable root account:Enabling and using the "root" user in OS X - Apple Support
I followed the instructions to sign in from the root account, got the lightroom application from my Time Machine backup, put it into the application folder, double-clicked on it, but then it just momentarily flashed full screen and disappeared again.
It just would be so much easier if I had a disk with the application or at least could download another copy.
Incidentally, the Lightroom uninstall folder backup is only an alias, so I can not use it.