Problem

When attempting to compute or validate a model using the Explicit (SWMM) solver, the below error appears, followed by a Bentley crash dialog. When clicking the details button in the crash dialog, the below details appear.

"Object Reference not set to an instance of an object."

Inner exception:
12/04/2017 11:57:23.30 System.NullReferenceException: Object reference not set to an instance of an object.

at Haestad.CivilStorm.Calculations.SWMM5.Domain.SWMMNumericalEngine.Validate(ModelingElementCollection scenarios)
at Haestad.StormSewerProduct.Support.Actions.Analysis.Calculations.SWMMValidateAction.ExecuteImpl(IQueryApplicationState queryApplicationState)
at Haestad.Framework.Support.Actions.ActionBase`2.Execute()
at Haestad.StormSewerProduct.Support.Actions.Analysis.Calculations.ValidateAction.ExecuteImpl(IQueryApplicationState queryApplicationState)
at Haestad.Framework.Support.Actions.ActionBase`2.Execute()
at Haestad.StormSewerProduct.Application.StormSewerProductParentFormUIModel.ExecuteCommand(CommandType type, Object data)
at Haestad.Drawing.UI.Integration.Support.Commands.RibbonCommand.Execute(Object parameter)
at Haestad.Framework.UI.Integration.RibbonUICommand.InvokeCommand(Object parameter)

Solution

This is a known issue that occurs when using the SWMM solver with one or more pumps that are missing their "downstream link" designation. Review the Pump flextable and add the "downstream link" field. For those whose "downstream link" is blank or set to an ID number instead of a label, right click on the row header, choose "zoom to", review and fix the "downstream link". Once all are fixed, the crash in question will no longer occur.

Defect # 591901

See Also