soap:ServerServer was unable to process request. ---> Unable to obtain object reference to Collaboration Manager service proxy.
Check if the Collaboration Manager Service is connected with the webapplication, where the CM is used.
Check if the proxy is enabled in the central administration under 'Manage WebApplications' --> Select WebApplication --> 'Manage Service-Connections'.
If the error still remains, please delete the CM Service Application and create a new one.
At last execute an IISRESET /NOFORCE.