Generate a Unique Decryption Key for Each Application (IIS 7)

Article
07/02/2012

Applies To: Windows 7, Windows Server 2008, Windows Server 2008 R2, Windows Vista

Generate a unique decryption key for each application when you want ASP.NET to create a random key. Local Security Authority (LSA) uses the application ID of each application to create this key. LSA then stores the key on your Web server.

Prerequisites

For information about the levels at which you can perform this procedure, and the modules, handlers, and permissions that are required to perform this procedure, see Machine Keys Feature Requirements (IIS 7).

Exceptions to feature requirements

None

To generate a unique decryption key for each application

You can perform this procedure by using the user interface (UI), by running Appcmd.exe commands in a command-line window, by editing configuration files directly, or by writing WMI scripts.

User Interface

To Use the UI

Open IIS Manager and navigate to the level you want to manage. For information about opening IIS Manager, see Open IIS Manager (IIS 7). For information about navigating to locations in the UI, see Navigation in IIS Manager (IIS 7).
In Features View, double-click Machine Key.
On the Machine Key page, under Decryption key, select the Generate a unique key for each application check box, and then click Apply in the Actions pane.

Command line

To generate a unique decryption key for each application, use the following syntax:

appcmd set config /commit:WEBROOT /section:machineKey /decryptionKey:IsolateApps

The variable decryptionKey is used to configure IIS to either generate a decryption key at runtime, generate a unique decryption key for each application, or both. The default value is AutoGenerate,IsolateApps.

Note

When you use Appcmd.exe to configure the <machineKey> element at the global level in IIS 7, you must specify /commit:WEBROOT in the command so that configuration changes are made to the root Web.config file instead of ApplicationHost.config.

For more information about Appcmd.exe, see Appcmd.exe (IIS 7).

Configuration

The procedure in this topic affects the following configuration elements:

<machineKey> element, defined in the Machine.config file.

For more information about IIS 7 configuration, see IIS 7.0: IIS Settings Schema on MSDN.

WMI

Use the following WMI classes, methods, or properties to perform this procedure:

MachineKeySection.ValidationKey IsolateApps flag

For more information about WMI and IIS, see Windows Management Instrumentation (WMI) in IIS 7. For more information about the classes, methods, or properties associated with this procedure, see the IIS WMI Provider Reference on the MSDN site.