No Anatoliy,
The name of the DLL id 3PartyDll.dll

Yes, I took care of case-sensitivity.
If you do not spell (case-sensitively) the function you get the error "Function no Found".



>The mistake is not in parameters you pass to an external function. This error message indicates that function Signal can not be found in external library.
>
>Note that in your declaration the library name is "3partyDll". I bet you missed a dot before "Dll".
>
>Otherwise note that external function names are case-sensitive.