LDAP request tracker 5.0.3

error when installing module RT::Authen::ExternalAuth::LDAP could someone help me to do the correct installation RT-5.0.3…

command
cpan[1]> install RT::Authen::ExternalAuth::LDAP

It’s been pulled into core so you don’t need to build/install it separately.
See docs/UPGRADING-4.4