COMException (0x80040154) in "Any CPU" .NET application

Symptom

You get a COMException(0x80040154) when running a .NET application compiled for "Any CPU" on 64-bit Windows.

Reason

Rfc Connector is a 32-bit COM library and cannot be called from 64-bit processes.

Solution

Change your project build target from "Any CPU" to "x86":

  1. From the toolbar in Visual Studio, select "Configuration Manager":
    Configuration Manager
  2. In the Configuration Manager, change the "Debug" and "Release" configuration's platform from "Any CPU" to "x86":

Additional Information

We cannot provide a 64-bit version of Rfc Connector, because SAP has not released a 64 Bit SAP GUI yet. As soon as a native 64-bit SAP GUI is available, we will release 64 bit version of Rfc Connector. According to SAP Note 1442028, a 64 bit version of SAP GUI can be expected in 2015.