Object Reference Error

[Memnoch1207]

I'm getting the following error

Object Reference not set to an instance of an object

On this line of code

Private Declare Function ImageDirectoryEntryToData Lib "dbghelp.dll" (ByVal pBase As Long, ByVal bMappedAsImage As Long, ByVal DirectoryEntry As Int32, ByRef Size As Long) As Long
 
Private Structure IMAGE_EXPORT_DIRECTORY
        Public Characteristics As Long
        Public TimeDateStamp As Long
        Public MajorVersion As Int32
        Public MinorVersion As Int32
        Public lpName As Long
        Public Base As Long
        Public NumberOfFunctions As Long
        Public NumberOfNames As Long
        Public lpAddressOfFunctions As Long
        Public lpAddressOfNames As Long
        Public lpAddressOfNameOrdinals As Long
    End Structure
 
Const IMAGE_DIRECTORY_ENTRY_EXPORT = 0
Private lngBaseAddress As Long
 
Dim pExportDirectory As Long
Dim lngSize As Long
 
pExportDirectory = ImageDirectoryEntryToData(lngBaseAddress, 1, IMAGE_DIRECTORY_ENTRY_EXPORT, lngSize)[color=red]<----- This line[/color]

I am creating an application that allows the user to load a .dll file via the OpenFileDialog control. Then they click a button to enumerate the Functions in that dll.

Any ideas why I would be getting this error??? I created this application just fine in VB6 and have made all the necessary modifications to rewrite it in VB.NET, but am getting this error for some reason???