Welcome message is a message application user will see on the log in page bellow the log in fields. You can change it in your Administration module under Setting.

For example, in our Polar Help Desk 5 development installation, we use it for quick log in, and it looks like:

 Password and Login: Administrator, Manager, Supporter, User, Anonymous 

In our Setting, under the Welcome message has been entered this:

 Login as: <a href="http://development.polarsoftware.com/ccnetphd/login?username=admin&  password=password">Administrator</a>,
 <a href="http://development.polarsoftware.com/ccnetphd/login?username=manager&password=password">Manager</a>,
 <a href="http://development.polarsoftware.com/ccnetphd/login?username=support&password=password">Supporter</a>,
 <a href="http://development.polarsoftware.com/ccnetphd/login?username=user&password=password">User</a>,
 <a href="http://development.polarsoftware.com/ccnetphd/login?username=anonymous">Anonymous</a>

You may change according to your wishes.