Diagnosis
A function module for managing parallel RFCs has discovered an internalerror. You can find an exact description of the error in the systemlog.
The connection from the application server to the message server isprobably damaged. Therefore the list of active application serverscannot be determined.

Procedure
Check the system log for corresponding error messages.
Use the diagnosis function in Transaction SM12 (choose Extras ->Diagnosis) to check that the message server is operating correctly.