[Microsoft][SQL Server Native Client 11.0]Connection is busy with results for another command

Creating a custom SQL Trigger in the Dynamics SL Application DB started causing this error when deleting lines items from Order Manager Sales Orders.

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SQL Server Message 93
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[Microsoft][SQL Server Native Client 11.0]Connection is busy with results for another command

  Debugging info: select * from soline where cpnyid= '0040' and ordnbr= 'O0016328' and lineref= '00001'
  Cursor(RefreshCursor) select * from soline where cpnyid= '0040' and ordn
  Optional info: SqlState = HY000 NativeError = 0 ErrorMsg = [Microsoft][SQL Server Native Client 11.0]Connection is busy with results for another command pcbErrorMsg = 93
ODBCRowNumber = -1 Column = -1 SSrvrLine = 0 SSrvrMsgState = 0 SSrvrSeverity = 0 SSrvrProcname =  SSrvrSrvname =

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OK
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The solution was to add a 'Set Nocount On' statement at the beginning of the Trigger definition.