Troubleshooting Group Policy

Administrator Enters Invalid Values
Group Policy administrative tools, such as the Group Policy Editor and the Group Policy Management Console, do not perform custom validations, so they will allow an administrator to enter an invalid value in a string field, such as an incorrect type name.

Only policies having valid values on all settings are applied, so when an invalid value is detected, an entry is written to the event log and the entire policy is ignored. The problem is logged to the event log.

Application Is Modified Without Generating New Group Policy Template
If the application is modified, some configuration elements may be replaced with new elements that have the same names, but different types. In this case, the manageable configuration source will look for the policies of the new element, but it will find policy settings for the original configuration elements, which may not match. Typically, this will result in missing values.

Policies Conflict to Produce Invalid Configuration
It is possible for different policies to conflict with one another. If this is the case, it will result in an invalid configuration after the Group Policy overrides are applied. This type of problem can easily occur, because different polices may be applied in different Group Policy Objects. In this case, the ManageableConfigurationSource instance does not detect an error. Typically, the consumer of the configuration settings logs the error.

Querying and Updating the WMI Repository

You can use Windows Management Instrumentation (WMI) to view and update a running application's configuration data when you use the Manageable Configuration Source to expose your Enterprise Library configuration. The Manageable Configuration Source reads information from the configuration file, applies any applicable Group Policy overrides, and exposes the configuration information to applications as a series of configuration class instances in the same way as the other Enterprise Library configuration sources.

However, the Manageable Configuration Source also exposes the configuration information through the .NET WMI 2.0 API and to the WMI Repository as a set of WMI classes that you can query and view. This allows administrators and users to examine configuration information using standard Windows-based management tools or code.

In addition, administrators and users can update the values of the WMI objects using standard Windows-based management tools or code. These changes update the configuration information exposed to the application by the Manageable Configuration Source, which also raises a ConfigurationChanged event that allows the application to react to the changes and reload the new configuration values.

Note:
You must have the relevant Windows permissions to update WMI objects. In addition, as changes pass back to the Manageable Configuration Source, it reapplies any relevant Group Policy overrides. If the change conflicts with a Group Policy setting, the Manageable Configuration Source will ignore the change and continue to expose the Group Policy-applied value.

Changes you make to the configuration exposed by the WMI objects are exposed by the Manageable Configuration Source and are visible in the application. However, they do not change the contents of the original configuration file. When the application restarts, or if you make changes to the configuration file contents, any updates made through WMI are lost. 

The following table lists the ways you can query and update values in the WMI Repository.