Utility Server version 6.2 and 6.3 had issues with the ldap.conf file being corrupted and breaking web logins. You may still be able to login to the shell. A fix was introduced for 6.3 with patch 6.3.2. Latest patch is 6.3.14.
https://support.avaya.com/downloads/...eleaseId=6.3.x
Try patching US from CDom.