NullReferenceException When calling a API

ASPI Declaration:

Code:

---


DWORD __stdcall SendASPI32CommandEx(LPSRB psrb)
        {
                // code
        }

---

VB Code:

'API Declaration
    <DllImport("ASPIshim", EntryPoint:="SendASPI32CommandEx")> _
    Public Function SendASPI32InquiryEx(ByVal hSRB As SRB_HAInquiry) As Integer
    End Function

VB Code:

'Calling----->
 
        MsgBox(modASPI.GetASPI32SupportInfoEx())
 
        Dim y As New modASPI.SRB_HAInquiry
 
        MsgBox(modASPI.SendASPI32InquiryEx(y)) '<---- NullReference Occurs here

Does modASPI.SRB_HAInquiry return some sort of default value? y is declared but not set to a value.

VB Code:

'API Declaration
    <DllImport("ASPIshim", EntryPoint:="SendASPI32CommandEx")> _
    Public Function SendASPI32InquiryEx(ByVal hSRB As SRB_HAInquiry) As Integer
    End Function

should have been...

VB Code:

'API Declaration
    <DllImport("ASPIshim", EntryPoint:="SendASPI32CommandEx")> _
    Public Shared Function SendASPI32InquiryEx(ByRef hSRB As SRB_HAInquiry) As Integer
    End Function