Bug in Mailman version 2.1.18-1

[Iva]

Tried to approve mails to the newsletter list and this message pops up:

Bug in Mailman version 2.1.18-1

We're sorry, we hit a bug!

Please inform the webmaster for this site of this problem. Printing of traceback and other system information has been explicitly inhibited, but the webmaster can find this information in the Mailman error logs.

I have no idea what to do.
We've recently moved our website to another server and cpanel.

[Mark Sapiro (msapiro)]

We need to see the error information from Mailman's 'error' log to diagnose this. The log is at /usr/local/cpanel/3rdparty/mailman/logs/error . If you are on a hosted server and don't have access, you will have to report this to the admins of the hosted server as only they will have the access necessary to diagnose and fix this.