When trying to establish connection with the organization service or discovery service in CRM 2011 you may receive the following exception
Unhandled Exception: System.ServiceModel.Security.MessageSecurityException: An unsecured or incorrectly secured fault was received from the other party. See the inner FaultException for the fault code and detail.
Solution: You need to Delete the device registration folder named LiveDeviceID in your profile folder C:\Users\<username>.
Alternatively you can navigate to “C:\Users\<username>\LiveDeviceID\” and rename the LiveDevice.xml file to LiveDeviceOld.xml.