Problem

When opening a model, one of the following error messages is generated:

"A procedure imported by 'Haestad.RealDWG.Interop', Version=8.4.0.50, Culture=neutral, PublicKeyToken=b4b808388021f6e' could not be loaded."

"A procedure imported by 'Haestad.RealDWG.Interop.dll' could not be loaded."

Background

This issue occurs if the program is not able to properly locate the RealDWG component, which is used to work with DXF files.

In one instance, this has been known to occur when running the latest release of SewerGEMS, SewerCAD, CivilStorm, and StormCAD, WaterGEMS, WaterCAD or HAMMER on Windows XP. The Autodesk RealDWG component required to open a DXF files as a background or for use in tools like TRex and ModelBuilder is no longer supported on Windows XP.

In addition to the RealDWG component no longer being supported on Window XP, Microsoft has also discontinued support for Windows XP (April 2014). For this reason the SELECTseries 4 release of the storm and sewer products and SELECTseries 5 release of Water products are no longer tested on Windows XP either.

Please note that because of the prevalence of Windows XP, you are still able to install the SELECTseries 4 releases of storm and sewer products , and SELECTseries 5 release of Water products on this operating system. However, it is highly recommended that you use a Windows 7 machine if possible.

Solution

Option 1 - Install on a more current operating system

The SELECTseries 4 release of the storm and sewer products and SELECTseries 5 release of Water products is officially tested and supported on Windows Vista, Windows 7, and Windows 8, among other operating systems. The best resolution to the issue would be to install the product on a more current operating system.

Option 2 - Don't use DXF files in the model

The SELECTseries 4 release of the storm and sewer products and SELECTseries 5 release of Water products will install on a Windows XP machine. If you have a current model that has a DXF file for a background, try moving the .stsw and the .stsw.mdb files (or .stsw and .stsw.sqlite files for the latest release) of storm sewer products and .wtg, .wtg.mdb (or .wtg, .wtg.sqlite files for the latest release) of water products to a new folder location and try opening theH model. It should open without an issue.

You will not be able to apply DXF background files to the model. In addition, DXF files used in ModelBuilder and TRex will generate error messages as well. Other modeling features will likely work okay, however please remember that installation on a Windows XP machine is no longer officially tested. For that reason, some unexpected issues may arise. So, again, it is highly recommended that you install the program on a current operating system.

Option 3 - Clean reinstallation

A variation of this error can also occurs in more recent versions such as the CONNECT Edition, which also mentions Haestad.RealDWG.Interop.dll. In one case, this was resolved with a clean reinstallation using these steps: How do I perform a clean uninstall and reinstall of the Hydraulic and Hydrology products?

See Also

The specified module could not be found (Exception from HRESULT: 0x8007007E)