From the forum: https://community.oracle.com/thread/4076952

Repro:

• Start a JVM with -Dcom.sun.management.jmxremote.authenticate=true -Dcom.sun.management.jmxremote.autodiscovery=true
  (This means that in order to connect to this JVM, you need to specify JMX username/password on the client side.)

• Open JMC, and see the JVM appear in the JVM Browser as a Discovered/JDP connection.
• Open the Properties of this JDP connection, and notice that there is no way of entering the username/password needed.

Workaround: Create a new connection with a custom JMX url taken from the properties of the JDP connection, add the username/password to this connection.

Extra note: The forum user wishes to have a credentials store in JMC, in order to avoid having to type in username/password for each connection (the user normally has 30+ connections)

ILW=HLM=P3