KB38 - Why do Excel SpeedGen Scripts execute so slowly?

Description

Excel SpeedGen ASP(.asp) or ASP.NET (.aspx) scripts execute slower than you had expected.

Solution

The first time you generate a Spreadsheet after IIS has started may be very slow. It should be much faster on subsequent generations.
If you are a trying out the Samples on the Web Page, then the longest part of the Generation process is the downloading to your browser and the opening in Excel itself. To see the real speed of Generation, just Right-Click the link and choose Save Target As.. . The spreadsheet has been generated by the time you see the Save As.. Dialog.

Other reasons for slowness can be found in KnowledgeBase Article KB34