Most static files such as images, CSS and Javascript includes seldom change in a production environment. Nevertheless, a web browser checks for a new version of these includes files each time it renders a page. By adding max-age to the HTTP Cache-Control response header, you can instruct the browser, to check for a new version, only if the set interval has passed.

Smartsite automatically adds this response  header to CSS and Javascript include files, but IIS doesn't do this by default.

The Scf folder includes only static files which are good candidates for this optimization.

You can set the max-age response header for the Scf site folder by executing the following commands:

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%systemroot%\system32\inetsrv\appcmd.exe set config "<sitename>/Scf" /section:system.webServer/staticContent /clientCache.cacheControlMode:UseMaxAge %systemroot%\system32\inetsrv\appcmd.exe set config "<sitename>/Scf" /section:system.webServer/staticContent /clientCache.cacheControlMaxAge:"1.00:00:00"

Replace <sitename> with the name of the site as displayed in the IIS manager. This sets the interval to check for new versions of the files in the Scf folder to once a day.

If you ever want to remove this repsonse header again, run these commands:

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%systemroot%\system32\inetsrv\appcmd.exe set config "<sitename>/Scf" /section:system.webServer/staticContent /-clientCache.cacheControlMode %systemroot%\system32\inetsrv\appcmd.exe set config "<sitename>/Scf" /section:system.webServer/staticContent /-clientCache.cacheControlMaxAge

To list the current IIS metabase settings for StaticContent use this command:

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%systemroot%\system32\inetsrv\appcmd.exe list config "<sitename>/Scf" /section:system.webServer/staticContent

After configuring max-age for the Scf folder, you should see this response header when interrogating the the response for a file in the Scf folder:

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HTTP/1.1 200 OK Cache-Control: max-age=86400

You can als control this setting from the IIS7 Manager:, select the Scf folder, then HTTP Reponse Headers in the Features view and then choose Set Common Headers from the Actions menu.

Note: by changes the path parameter for appcmd, you can override this setting for subfolders and/or individual files.