Configure the HTTP Expires Response Header (IIS 7)

1. Open IIS Manager and navigate to the level you want to manage.

2. In Features View, double-click HTTP Response Headers.

3. On the HTTP Response Headers page, in the Actions pane, click Set Common Headers.

4. In the Set Common HTTP Response Headers dialog box, select the Expire Web content check box and select one of the following options:
* Select Immediately if you want content to expire immediately after it is sent in a response.

* Select After if you want the content to expire periodically. Then, in the corresponding boxes, type an integer and select a time interval at which content expires. For example, type 1 and select Days if you want the content to expire daily.

* Select On (in Coordinated Universal Time (UTC)) if you want the content to expire on a specific day and at a specific time. Then, in the corresponding boxes, select a date and time at which the content expires.

5. Click OK.

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