Error message when you try to save a file in Excel 2007 or in Excel
2003: "You are attempting to save a file that is blocked by your
registry policy setting"
http://support.microsoft.com/kb/945797

Ken Warthen wrote:

I'm trying to convert an Excel worksheet to a Lotus 123, wk3, file format.
I've had to use Excel 2003 as Excel 2007 no longer appears to offer the Lotus
123 file formats. When I do the SaveAs command in Excel 2003 an error is
generated saying "You are attempting to save a file type that is blocked by
your registry policy setting."

Does anyone know a workaround for this issue?

Ken