CS4: export to pdf problem using COM in vb.net

Hi,

I try to export to a pdf in a vb.net console app but it keeps giving me an error. The rest of my code works fine and when I save the document I can see that everything went well.

Basically my code for exporting is:

mydoc.Export(InDesign.idExportFormat.idPDFType, pdfPath, myapp.PDFExportPresets.Item("[Press Quality]"), False, Nothing, False)

But I keep receiving the following error "Conversion from type 'PDFExportPreset' to type 'Boolean' is not valid."

I've been trying to switch param's around but nothing seems to help.

Thanks in advance