How do you set the expiry date or a maximum age in the HTTP headers for static resources in IIS

Question

I am using IIS 6 and IIS 7 as a web server.

After running Google page speed online , it remarks that I should be: Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.

And it lists a lot of plain images , my javascript files and the style sheets.

How can I set this expiry date for these static files ? I thought this was done automatically by the browser ?

Answer 1

Leverage browser caching:

Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.

http://code.google.com/speed/page-speed/docs/caching.html#LeverageBrowserCaching

To set an expiry date or a maximum age in the HTTP headers for static resources

Open IIS manager-> Click your site-> Click the HTTP Response Headers in the home page-> Click the Set Common Headers on the Actions panel -> Check Expire Web Content -> Set After 7 days (as suggested for in the page speed analysis "Specify an expiration at least one week in the future for the following resources"

http://technet.microsoft.com/en-us/library/cc770661%28WS.10%29.aspx