Administrator cannot login to SGD

 Hello,

I have installed SGD, and have been using it successfully in my test enviornment for two weeks.  The system is still running, but starting a few days ago, I have been unable to log into the webtop or administration console using the administrator's account. 

Both present the error  "Invalid credentials."

I have tried all of the passwords on the network, but none of them are working.  I am still able to log in with my user account, and am able to successfully launch applications.   My users are using LDAP Authentication, i want to know how to reset the admin password please.