Re: Signal 11 Error on triggering Close action web service using SOAP UI
A Signal 11 error is a general failure in the RTE/binary layer that can be caused by many things, including: software defect, memory issue, or corrupt/bad data.
As Abhijit mentioned, reviewing the sm.log file is the next step as it should contain a stack trace/thread dump related to the error. If the issue can be replicated, consider tracing the action as this will help identify the failure point in the work-flow.
Assuming the cause is not obvious from the log and it is not a published known issue, a ticket should be opened with Customer Support to analyze the trace.