Symptoms

All task email notifications from K2 are not being sent out.
Below is the K2 server logs
"6842704","2014-12-02 12:06:38","Error","MessageBus","61007","SendMessageException","MessageBusRuntime","61007 Permanent failure sending message TEst Email: System.Exception: No destinations could send the message TEst Email.
at SourceCode.MessageBus.Server.MessageBusRuntime.SourceCode.MessageBus.IMessageDestination.Send(String title, MessageExtendedInformation extended, IEnumerable`1 attachments, MessageBodyReadere] messageBodies)","","","rok2dev02:C:Program Files (x86)K2 blackpearlHost ServerBin","6842704","22db5caa9af24a3793a906878fb72673
 

Diagnoses

Comparing the connection strings that were available in the K2ConnectionStringEditor.exe tool located at "C:Program Files(x86)K2 blackpearlHost ServerBin" vs the K2HostServer.exe.config file, we noticed that there were only EWS destination connection strings available.

 

Resolution

As such, we modified the K2HostServer.exe.config and updated the node "<add path="SmartActionsSMTP" />" to "<add path="SmartActionsEWS" />" to reflect the available EWS connection strings:

<sourceCode.smartActions.directoryCatalog>
  <catalogs>
     <add path="SmartActions" />
     <tadd path="SmartActionsEWS" />
  </catalogs>
</sourceCode.smartActions.directoryCatalog>

A restart of the K2 service was necessary.