Some times WHM won’t update license for some reason, show license expired message when login to Cpanel/WHM/Webmail etc..

First verify Your server have valid cpanel license by going to following site.

http://verify.cpanel.net

Enter your server IP to verify server have valid license. If your license is fine, login in to server as user root and run

/usr/local/cpanel/cpkeyclt

Example

[root@server78 ~]# /usr/local/cpanel/cpkeyclt
Updating cPanel license...Done. Update succeeded.
Building global cache for cpanel...Done
[root@server78 ~]# 

Some times firewall can block access to cpanel server, in that case, you should check firewall rules. This you will be able to find by checking /var/log/messages.

If you have CSF firewall, run

csf -x

For iptables, run

iptables -F