WHM login attempt reports "The login is invalid"

Symptoms

When attempting to log in to the WHM or cPanel interfaces, the error "The login is invalid" is reported at the top of the page.

Cause 

This error indicates that the credentials used in your authentication attempt were rejected. This is commonly caused by either entering an invalid password or by an authentication attempt being blocked by cPhulkd. 

Resolution

1. Confirm that the correct password is being used.

2. Log in as the root user and run the following command to ensure that your IP is whitelisted in cPHulk:

   # /usr/local/cpanel/scripts/cphulkdwhitelist $IP

   Note: Replace the example($IP) with your actual IP address.