You see a yellow triangle with an exclamation mark (a warning icon) next to the name of the peer you want to communicate with and no traffic is going through between the peers.

You generally see a warning next to a peer if the security settings block traffic between peers.

Click on the warning icon and then click on the description of the problem. This opens the Peer Properties window. The errors are marked in red.

• If there is a connection error, on the Settings tab, click the change link next to Traffic. Then change the setting to Block unsecured or Allow all.
  Important: We do not recommend that you select Allow all.
• If there is an authentication error, the peer is untrusted by your client. Click on the details link next to the error and then click on the description of the error. Then click Trust to authenticate the peer.