Pivotal Cloud Foundry® (PCF) versions 1.7, 1.8, 1.9, 1.10, and 1.11
In PCF 1.7 and versions above than 1.7, Ops Manager comes with security features. When configuring Ops Manager Director, you are required to set the "Decryption passphrase value". It is used as the key to encrypt and decrypt the installation information.
If you forget the decryption password, there is nothing you or Support can do. The passphrase cannot be recovered. It is not a password that is stored in the database. Because of the nature of encryption, there' is no way to recover Ops Manager without having the passphrase.
Note - Ensure that your key is safe. Back it up somewhere safe like using the password manager. This key is incredibly important!