Load pal files on vb.net

Question

Im having this error on vb.net "unable to read beyond the end of the stream". It happens when i compile the program and it breaks in there.

Dim red As Byte = br.ReadByte()
Dim green As Byte = br.ReadByte()
Dim blue As Byte = br.ReadByte()
Dim flags As Byte = br.ReadByte()

But i will also give all the code:

Public Shared Function LoadPal(filename As String) As List(Of Color)
        Dim colors As New List(Of Color)()
        Dim stream As New FileStream(filename, FileMode.Open, FileAccess.Read, FileShare.Read)
        Using br As New BinaryReader(stream)
            ' RIFF header
            Dim riff As String = ReadByteString(br, 4)
            ' "RIFF"
            Dim dataSize As Integer = br.ReadInt32()
            Dim type As String = ReadByteString(br, 4)
            ' "PAL "
            ' Data chunk
            Dim chunkType As String = ReadByteString(br, 4)
            ' "data"
            Dim chunkSize As Integer = br.ReadInt32()
            Dim palVersion As Short = br.ReadInt16()
            ' always 0x0300
            Dim palEntries As Short = br.ReadInt16()

            ' Colors
            For i As Integer = 0 To palEntries - 1
                Dim red As Byte = br.ReadByte()
                Dim green As Byte = br.ReadByte()
                Dim blue As Byte = br.ReadByte()
                Dim flags As Byte = br.ReadByte()
                ' always 0x00
                colors.Add(Color.FromArgb(red, green, blue))
            Next
        End Using
        Return colors
    End Function


 Private Shared Function ReadByteString(br As BinaryReader, length As Integer) As String
        Return Encoding.ASCII.GetString(br.ReadBytes(length))
    End Function