Virtualmin Install failed

Have installed the manual way and by using the script. No matter what I do still can't actually fully login to Virtualmin. Username and password is accepted and all I'm seeing is a blue circular motion on the screen and NEVER actually logs in. Was getting an error message such as missing "Perl module Authen" and I installed that. As for a ptr record don't understand why I can't login to Virtualmin by ip as I can do that with Webmin. Using Centos 6.8 & 7 and still get the same result as listed above. Any help would be appreciated!