User asserted identity not in FIM Service An unauthenticated user requested to reset the password for a user who is not in ...

User asserted identity not in FIM Service
An unauthenticated user requested to reset the password for a user who is not in the FIM Service.
The user's identity was: {0}
The user's IP address was: {1}
Possible causes include: (1) the asserted Active Directory identity has not been synchronized to the FIM Service; (2) user error inputting their identity, or (3) malicious user attempting to enumerate valid identities and/or reset password for other users.