It's a lot of code, but this is the gist of it.

In Form1 I have:

Code:
Imports WindowsApplication1.FileStuff
Public Class bTest
    Dim Curves As New List(Of stcCurve)
    Dim Bias As New stcCurve
    Dim Temp As New stcCurve
    Dim Power As New stcCurve
    Dim BiasPoints = New PointPairList()
    Dim PowerPoints = New PointPairList()
   .......
   Public Sub SetUpCurves()
        Bias.CurveColor = Color.AliceBlue
        Bias.CurveName = "Bias Current"
        Bias.CurveSymbol = SymbolType.Circle
        Bias.CurvePoints = BiasPoints
        Curves.Add(Bias)

        Power.CurveColor = Color.AliceBlue
        Power.CurveName = "Power Dissipation"
        Power.CurveSymbol = SymbolType.Circle
        Power.CurvePoints = PowerPoints
        Curves.Add(Power)

        Temp.CurveColor = Color.AliceBlue
        Temp.CurveName = "Power Dissipation"
        Temp.CurveSymbol = SymbolType.Circle
        Temp.CurvePoints = PowerPoints
        Curves.Add(Temp)
    End Sub
   .....
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'set up the graph
        'set curve attributes
        Call SetUpCurves()
        For Each myCurve As stcCurve In Curves
            MessageBox.Show(myCurve.CurveName)
        Next
    End Sub
End Class
... and that's fine.

Then in another module I have:

Code:
Imports WindowsApplication1.bTest
Public Class FileCSV
     ......
     Public Sub EnableCheckBox(ByVal CurveName As String)
                Select Case CurveName
                    Case bTest.Bias.CurveName 'this gives the error message
                        bTest.cbxRefIb.Enabled = True
                        bTest.cbxRefIb.Checked = False
                    Case bTest.Power.CurveName 'this gives the error message
                        bTest.cbxRefPc.Enabled = True
                        bTest.cbxRefPc.Checked = False
                    Case bTest.Temp.CurveName 'this gives the error message
                        bTest.cbxRefTc.Enabled = True
                        bTest.cbxRefTc.Checked = False
                End Select
            End Sub
        End Class
The error message is:

Error 2 'WindowsApplication1.bTest.Bias' is not accessible in this context because it is 'Private'.