On a fresh install the database USERS table is populated with a user named 'admin' with the password 'admin'. The password however is MD5 encoded.
To reset the admin password you need access to the everything HelpDesk database with rights sufficient to update the USERS table and a general knowledge of how to run SQL commands on your database of choice.
The following SQL will set the password back to the default 'admin'.
update USERS set PASSWORD = '21232f297a57a5a743894a0e4a801fc3' where LOGINID = 'admin';
You should now be able to log into everything HelpDesk as admin/admin. Be sure to change the admin password by clicking on the "SYSTEM ADMIN" link in the header to something a little more memorable.