Update php and upgrade: server error on login

[clemphoto]

My site is http://clemsonphotoclub.com/coppermine/index.php. It was operating correctly with 1.56 and php5.6. I used the upgrade/install aid to go to version 1.6.03 after setting php version to 7.3 in cpanel. While the site appears to work correctly in most ways, login does not. Attempting login results in Internal Server Error. What other information do you need to be able to provide advice for this problem?
Del

[ron4mac]

Your CPG install seems to be bridged to a Simple Machines Forum (SMF). It is SMF that is failing. Try backing off your PHP version or get SMF fixed/upgraded.

[clemphoto]

Thanks, and I have just confirmed that smf fails this way when I am using php 7. Back to 5.6 and it works ok, so I need to update smf.

My system no longer needs smf or bridging, but if I disable bridging will I lose user information and folders? Should I take this question to the bridging forum?

I appreciate very much hearing from you this quickly.
Del