Error including the required files:

Be sure you uploaded UltBB.setup, Styles.file, mods.file and forums.cgi in ASCII/Text mode to your CGI directory. [This is a manual setting on your FTP software]

Make sure spelling and case are correct: UltBB.setup not ultbb.setup.

Here is the message returned from UBB:

Can't locate UltBB.setup in @INC (@INC contains: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.34.0 /usr/local/share/perl/5.34.0 /usr/lib/x86_64-linux-gnu/perl5/5.34 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl-base /usr/lib/x86_64-linux-gnu/perl/5.34 /usr/share/perl/5.34 /usr/local/lib/site_perl) at cpanel.cgi line 38.