DLP has a utility called AdminPasswordReset.exe.
There is no method to recover a lost password, but you can use this utility to assign a new password.
Supported versions of DLP (15.8 and above, currently)
Important Note - This tool resolves the following issues:
1. Lost Administrator password
2. Misconfigured Single Sign On (everyone configured for SSO and no one can log in)
Tool prerequisites & results:
This can be done with a command-line tool as follows:
AdminPasswordReset.exe -dbpass <oracle "protect" password> -newpass <new admin password> (Windows)
./AdminPasswordReset.exe -dbpass <oracle "protect" password> -newpass <new admin password> (Linux)