I am using wwDotNetBridge. Work with a couple of .net libraries Charge the same way both

loBridge.loadassembly("HasarLibreriaFiscal3561.dll")
oPrinter = loBridge.CreateInstance("hfl.argentina.HasarImpresoraFiscalRG3561")

loBridge.loadassembly("FusionClass.dll")
oFusion = loBridge.CreateInstance("FusionClass.Fusion")

With the "oFusion" object I have no problems working. It's not the same with the "oPrinter" object. It may be because the dll ("HasarLibreriaFiscal3561.dll") es comvisible = .f. ??

Is there any way to load a library of this type? How do I know if the library can be used or not?

Look at the error message to see what's wrong. Most likely you're not loading a dependency or accessing an invalid constructor signature for the .NET object.

+++ Rick ---