If you experience difficulty when you attempt to switch between cPanel accounts, or when you log in to and out of your webmail account, your server may use HTTP basic authentication. If a server uses HTTP basic authentication, most browsers will not log out of a session until the user closes their browser, regardless of whether they click Log Out. This can make it difficult to switch between webmail and cPanel accounts.
Note:
This is a fundamental HTTP basic authentication issue. It is not unique to cPanel. For additional information, read Wikipedia’s Basic Access Authentication article
How to enable HTTP basic authentication
Warning:
We strongly recommend that you do not enable this setting.
HTTP basic authentication is set to Off by default. You cannot enable HTTP basic authentication through the WHM interface.
To change your server’s HTTP basic authentication setting manually in the cpanel.config file, perform the following steps:
.1With your preferred text editor, open the /var/cpanel/cpanel.config file via an SSH session as the root user.
.2Change the skiphttpauth=1 setting to skiphttpauth=0