This exception is thrown when the particular flavor of authentication requested is not supported. For example, if the program is attempting to use strong authentication but the directory/naming supports only simple authentication, this exception would be thrown. Identification of a particular flavor of authentication is provider- and server-specific. It may be specified using specific authentication schemes such those identified using SASL, or a generic authentication specifier (such as "simple" and "strong").

If the program wants to handle this exception in particular, it should catch AuthenticationNotSupportedException explicitly before attempting to catch NamingException. After catching AuthenticationNotSupportedException, the program could reattempt the authentication using a different authentication flavor by updating the resolved context's environment properties accordingly.

Synchronization and serialization issues that apply to NamingException apply directly here.