Isolating Applications in IIS 6.0

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1


This feature of IIS 6.0 is available only when IIS is running in IIS 5.0 isolation mode.

Isolating applications means configuring them to run in a process (memory space) that is separate from the Web server and other applications. You can configure applications to have one of three levels of application protection:

  • Low (in-process) application protection.

  • Medium (pooled) application protection.

  • High (isolated) application protection.

Note that server-side include (SSI) and Internet Database Connector (IDC) applications cannot be run in a memory space that is separate from the Web server.


You must be a member of the Administrators group on the local computer to perform the following procedure or procedures. As a security best practice, log on to your computer by using an account that is not in the Administrators group, and then use the runas command to run IIS Manager as an administrator. At a command prompt, type runas /user:Administrative_AccountName "mmc %systemroot%\system32\inetsrv\iis.msc".


To set or change the level of application protection

  1. In IIS Manager, expand the local computer, right-click the Web site or the starting-point directory for an application, and then click Properties.

  2. Click the Home Directory, Virtual Directory, or Directory tab. If you are in the directory that is listed as the Starting Point directory, the Application name box is filled in.

  3. In the Application protection box, click the appropriate level of protection.

  4. Click OK.

The Web server finishes processing any current requests for the application before it creates a separate process. At the next request for the application, the application will run in the appropriate memory space.

You can also configure isolation by updating the AppIsolated metabase property setting for each application. For information about how to do this, see the AppIsolated Metabase Property, and Code Examples to Configure Metabase Properties.


If you need to stop an application that has isolation set to Medium (pooled) or High, see Stopping Isolated Applications.