how to replace strange macintosh characters with a different character

I have a tab-delimited file that came from a Mac OS-X program with a *.DAT extension.
I have no problem reading it into a windows app I am writing except for one small issue:
It carries over some characters that I have no idea what the correct character code is in order to remove it.  Some text has bullets in it and I thought they were ASCII CHR(165) as I've seen in smoe other posts, but that is not the case even though they show up as the Yen symbol when opened in WordPad, but show up as squares in everything else.  Doing research, the Yen symbol is indeed ASCII 165.
There must be another yen symbol somewhere in Unicode space OR the VB.NET 2.0 string type is not actually Unicode OR the REPLACE function does not recognize Unicode.
I've tried every possible combination of replace I can think of:
Microsoft.VisualBasic.Replace(mystring, CHRW(165), "*")
Microsoft.VisualBasic.Replace(mystring, CHR(165), "*")
Microsoft.VisualBasic.Replace(mystring, "¥", "*")
mystring.Replace("¥", "*")
mystring.Replace(CHR(165), "*")  
mystring.Replace(CHRW(165),"*")
with no luck.
To make sure the functions were working, I put in a common letter and tested it, and it worked just fine.
The file is Tab-delimited format and opens fine in Excel 2003 without importing with a *.DAT extension.
The Yen symbol is just one of the many codes I cannot determine even though every reference claims it is ASCII 165 or Unicode 00A5.
I'd prefer to simply delete all the characters, but some, I can tell are bullets or superscripts and others that do not agree with Windows codesets.

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Dim coldelim As String = vbTab
        Try
            Dim filestream As StreamReader = File.OpenText(localfilepath)
            Do Until filestream.EndOfStream
                Dim line As String = Microsoft.VisualBasic.Replace(filestream.ReadLine, ChrW(165), "*", , , CompareMethod.Binary)
                Dim ARYfield As Array = line.Split(coldelim)
                Dim row As DataRow = dt.NewRow()
                For i As Integer = 0 To UBound(ARYfield)
                    If IsDBNull(ARYfield(i)) Then
                        row(i) = String.Empty
                    Else
                        row(i) = CType(ARYfield(i), String)
                    End If
                Next
                dt.Rows.Add(row)
            Loop
            filestream.Close()
            success = True
        Catch ex As Exception
            success = False
        End Try