Enable content expiration in IIS to optimize ASP.Net website

Enable content expiration in IIS to optimize ASP.Net website
Default setting is Off.

To set the expiration of Web site content

1.	In IIS Manager, double-click the local computer; right-click the Web Sites folder, an individual Web site folder, a virtual directory, or a file; and then click Properties.
2.	Click the HTTP Headers tab.
3.	Select the Enable content expiration check box.
4.	Click Expire immediately, Expire after, or Expire on, and type the appropriate expiration information in the corresponding boxes.

http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/0fc16fe7-be45-4033-a5aa-d7fda3c993ff.mspx?mfr=true