When an inventory group is created by hardware inventory, it permanently changes the schema of the Configuration Manager 2007 (ConfigMgr) database. Occasionally, it is necessary or desirable to remove inventory group definitions to reduce the amount of space being used by inventory or when an inventory group is no longer being collected, or if it was collected by accident.

Sometimes an inventory group definition conflicts between sites when each site uses a different table name. For example, the parent site might use a table ending in _DATA and a child site might use a table ending in _DATA2. This prevents collections defined at the parent site from being evaluated at the child site. This might occur when one or more inventory groups are collected with the same group name but have different class names. Removing both groups and changing one of the group names corrects the problem.

This tool update performs a better cleanup than earlier versions. It lists collections affected by the change, removes only the history data or the whole tables, views and stored procedures for a group, and lists available groups. Additionally, it prevents users from removing predefined groups.

Main Features

Inventory Cleanup

In addition to removing the entries in the GroupMap and AtttributeMap tables, it also removes the inventory stored procedures, schema views and tables.

List Affected Collections

If an inventory group is removed, collections that reference the table of the group cause errors when they are evaluated. These collections should be removed or redefined.

Remove History

Inventory that changes frequently can generate large amounts of inventory history. By removing history data, the database size is reduced. The processing time that is required to maintain the database is also reduced by removing those data.

System Requirements

Supported Operating Systems: Windows Server 2003; Windows Server 2008; Windows Server 2008 R2

Supported Site System: System Center Configuration Manager 2007 SP2 or System Center Configuration Manager 2007 SP1

Additional Requirements: DelGrp.exe must run on the site server by a user with administrator credentials to the Configuration Manager 2007 site database.


Delgrp /?

Delgrp /L

Delgrp <Inventory Group Class Name> [/C | /H]

Command-Line Options

Option Description


Lists available groups for deletion, displaying the approximate number of rows in the data table of the group, the approximate number of rows in the history table of the group, and the class name. Predefined groups are not listed.


Displays the collection ID and name of collections that would be affected by the group removal. The group is not removed. This option also displays predefined inventory groups.


Only the history data is removed for the group.


Deletes the group if a group name is specified. Otherwise, the command-line options are displayed.


Displays the command-line options.


To remove unused inventory classes from the Configuration Manager site database

  1. Stop the SMS_EXECUTIVE service.

    The SMS_EXECUTIVE service must be stopped during the procedure, and then restarted afterwards, or errors might occur.
  2. Use the /L option to identify classes that can be deleted by this tool.

  3. Use the /C option to ensure that no collections will be affected.

  4. Remove the class.

  5. Start the SMS_EXECUTIVE service.



  2. DelGrp /L




Default classes that are created by Configuration Manager 2007 Setup cannot be removed or altered.

You must have db_owner permissions for the Configuration Manager 2007 database to remove history data or classes.