The link seems to be correct however, because if I don’t do this I have one more error. Any idea to fix this error ?
Try to rebuild ndisapi.dll with your compiler and then link to your application. Different C++ compilers use different name mangling for C++.
I also have another question : I ran listadapters.exe and it shew me a list of interfaces. Then, I plugged a 3G key and ran again the program : it shew me the same list as before. Is this normal ?
In Windows all WAN devices are visible as NDISWANIP virtual Ethernet interface, so adding another modem does not change the list of adapters. If you establish the connection using 3G modem you will see it in the list of the active WAN links.