I had thought SP2 corrected that uissue:
Do you mean .asp rather than .asp?
If so, this might help, although I'd suggest either the repair tool or upgrade to IE6:
Internet Explorer Prompts the User with Two Open or Save Dialog Boxes
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The information in this article applies to:
Microsoft Internet Explorer version 5 for Windows 2000
the operating system: Microsoft Windows Millennium Edition
Microsoft Internet Explorer version 5 for Windows NT 4.0
Microsoft Internet Explorer version 5 for Windows 98
Microsoft Internet Explorer version 5 for Windows 95
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SUMMARY
You may be prompted with two Open or Save dialog boxes when you use Internet Explorer to connect to certain Web pages under the following conditions:
Neither a file name nor an extension is specified in the Uniform Resource Locator (URL) of a Get request.
-and-
The server replies with both a registered "Content-Type" header and the "Content-Disposition: attachment; filename=" header which specify the file name that you want.
MORE INFORMATION
Because neither a file name nor an extension is defined in the URL for the Get request, Internet Explorer does not know what type of data to expect in the response; therefore, Internet Explorer sets a default Octet-Stream data type.
This data type causes Internet Explorer to display the Open or Save dialog box with the file name information that indicates the Active Server Pages (ASP), Common Gateway Interface (CGI), or PerlScript file that had been located in the URL for the Get request.
If you open the document, Internet Explorer examines the data type which is currently set for Octet-Stream. Because this is an ambiguous data type and there is no file name or extension information in the URL, Internet Explorer looks for additional headers and finds the "Content-Type" and "Content-Disposition: attachment; filename= " headers.
Because the file name and extension is specified in the "Content-Disposition: attachment; filename=" header and the data type is defined in the "Content-Type" header, you are prompted with a second Open or Save dialog box that contains the correct file name information.
reghakr