Filter problem

[syc]

I'm facing a problem when i write code for Filter on Report_Open

Private Sub Report_Open(Cancel As Integer)

Me.Filter = "Lookupcode = 'ILCharges' And ParamValue NOT IN ('3')"
Me.FilterOn = True

End Sub

This code looks no problem but when i run it, an error message display said that:
"The setting you entered isn't valid for the property"
And this is a subreport.

Thanks,
syc