How to set the default "Save as type" for an excel file from C#?

I'm new to .NET and I'm using "workbooks.open" method and opening an excel file. The excel file get's opened and I'm able to enter data. When I choose "File--> Save as", the default "save as type" in the dialog box is shown as "tab delimited(txt)" file. It should be default Excel. How to set it from C#?

But when I open an excel file normally and choose "File-->Save as", the "save as type" is showing the correct default type. Could anybody provide their opinion?

[582 byte] By [UG] at [2008-1-9]
# 1
See http://msdn.microsoft.com/newsgroups/default.aspx?dg=microsoft.public.officedev&lang=en&cr=US

for discussions on programming the various Office programming models.

PeterRitchie at 2007-10-2 > top of Msdn Tech,Feedback for forums and MSDN websites,Off-Topic Posts (Do Not Post Here)...