"COM Error Not Documented" when opening OpenFlows product

Product(s): SewerGEMS, SewerCAD, StormCAD, CivilStorm, WaterGEMS, WaterCAD, HAMMER
Version(s): and (for Storm and Sewer products); build,, and (for Water products)
Environment:  Windows 7 64 bit
Area:  Installation

Error or Warning Message

When opening SELECTseries 3 version of a OpenFlows product (or earlier), the following error message is generated:

Haestad.Domain.DaoInterop.DAOException: COM error not documented

   at Haestad.Domain.DaoInterop.InteropLibrary.ThrowCOMException(_com_error* e)
   at Haestad.Domain.DaoInterop.DaoDatabase.CreateDatabase(String fileName, CultureInfo locale)
   at Haestad.Domain.LibraryObjects.JetAppSettings.OpenRegistryDatabase(String fileName)
   at Haestad.Domain.LibraryObjects.EngineeringLibraryService.OpenImpl()
   at Haestad.Domain.LibraryObjects.EngineeringLibraryService.EngineeringLibraryTypeNames(HmiProductBeta product)

This is sometimes followed by the following message:

Database format not recognized. It could not be opened.


This error may occur if the 64-bit version of the OpenFlows product has been installed along with a conflicting version of Microsoft Office. When installing the software on a 64-bit operating system, the program should detect the presence of the 32-bit version of Microsoft Office and force the software to install as a 32-bit application. The reason for is a Microsoft Office component called Access Database Engine. The 32-bit version of Microsoft Office will have the 32-bit version of the Access Database Engine.

On rare occasions, the 32-bit version of the Access Database Engine is not properly idenified. When this occurs, the 64-bit version of the product is installed and used in the Desktop shortcut. Since the 64-bit version will conflict with the 32-bit version of the Access Database Engine, the error message is generated.

This is a rare issue that will only occur the the SELECTseries 3 versions of the OpenFlows products and only on a 64-bit operating system with 32-bit Microsoft Office installed.

Note that this problem will no longer occur, as of the SELECTseries 4 versions of WaterCAD, WaterGEMS and HAMMER (or later). The reason is because a SQLite database is now used instead of an Access Database, eliminating the dependency on the Access Database Engine for opening a file. This also applies to the SELECTseries 4 release of StormCAD, SewerCAD, SewerGEMS and CivilStorm. 

How to Avoid

Primary Option: Upgrade to the latest version of the program

The SELECTseries 4 and later versions of the Water products and the Storm and Sewer products will not see this issue. Upgrading to the latest version of the software will eliminate this error completely and provide you with all of the latest updates and tools the programs have to offer. You can find the steps to upgrade to the latest version at the following link: Download OpenFlows | Hydraulics and Hydrology software.

Secondary Option: Creating new shortcut to 32-bit version of the product

If you cannot upgrade, the next best workaround is as follows:

1) Open My Computer and navigate to installation directory, typically similar to C:\Program Files (x86)\Bentley\(product name)
2) Open the .exe file (SewerGEMS.exe for SewerGEMS.) This is 32-bit version.
3) If the program opens without any error, right-click on the .exe and click on Copy.
4) Go to the Desktop, right-click, and select "Paste shortcut".

Another variation of the above is described below:

1) Locate the programs icon on your desktop and right click on it.

2) Select "Properties" and click on the Shortcut tab.

3) Locate the target file path the program is pointing to and change it from:  "C:\Program Files (x86)\Bentley\<ProductName>\x64\<ProductName>.exe"  to  "C:\Program Files (x86)\Bentley\<ProductName>\<ProductName>.exe" . All you are doing is removing the "/x64" from the file path so the icon now points to the 32 bit executable.

If 32-bit version of the OpenFlows product could not open from the program files directory, try reinstalling it. If you must use the 64-bit version of your OpenFlows product (such as for integrating with the 64-bit version of AutoCAD), then this workaround will not work.


Other Options 

Also, you have the following other options, the above steps are not feasible:

1) Upgrade to the SELECTseries 4 version of the product. A SELECTseries 4 release of all Water, Storm, and Sewer products is now available. This is option is highly recommended since the SELECTseries 4 release of the products will install as a 64-bit application on any 64-bit Windows machine. 

2) Uninstall 32-bit Office

3) Upgrade to 64-bit Office

4) Install the 64-bit version on a Virtual Machine (such as Windows 7's "XP Mode")

5) Try forcing the OpenFlows product installer to only install the 32-bit version. Details can be seen here. This option won’t work if you need the 64-bit version for some reason, such as for AutoCAD integration.

6) Try uninstalling the 64-bit Access Database Engine, then change the OpenFlows product shortcuts to point to the 32-bit version (the .exe under the root folder, not the x64 folder). Again, this won’t help if you need to integrate with 64-bit AutoCAD.

7) Try uninstalling Microsoft Office completely (including the 32-bit Access DB engine), then reinstall the OpenFlows product, then reinstall Office. The conflict happens when the 64-bit MS Access database engine is installed second, so this may work. IMPORTANT: this workaround is not tested so we cannot guarantee it will work.

See Also

Sometimes the error could be occurring because of unregistered DAO. Please see the link below:

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