Invalid class string


We use a .NET component to perform certain tasks, and we call this component from our COBOL program.

When installing on a customers place, we experienced that it worked on two machines, and two generated an error. The error was

"Invalid class string (Exception from HRESULT: 0x800401F3 (CO_E_CLASSSTRING))"

This happened during the CREATE verb.

The component is installed on the users %TMP%  area, by a automatic install routine.

The install routine also installs a xml-file containing the filepath to the component, and this xml-file is refered in the CREATE verb as "FILE-PATH" option.

Installation of both files (component and xml-file) is verified as correct, and the path in the xml-file is also correct. The path in the CREATE verb is also verified as correct.

What is the reason, and more importantly, what is the solution?


AcuCobol compiler version: 9.1.0

AcuCobol runtime version: 9.1.0

.NET Frame version installed: 4.0 (the same on all four machines, also those that works)


I hope someone else have experienced this, and can give me a clue.


Regards Dagl

1 Reply
Micro Focus Expert
Micro Focus Expert

RE: Invalid class string

This error occurs when AcuToNet.dll is not registered.

regasm20acu /register /codebase AcuToNet.dll

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