Open Active Directory Users and Computers.

To open Active Directory Users and Computers, click Start, point to Administrative Tools, and then click Active Directory Users and Computers.

You can also open Active Directory Users and Computers from within Server Manager, by expanding Roles and then Active Directory Domain Services in the hierarchy pane, and then selecting Active Directory Users and Computers.

In the console tree, click the Users folder.

In the details pane, right-click the group you want to administer, and then click Properties.

Click the UNIX Attributes tab.

In the GID (Group ID) box, type the new group identifier (GID) for the group.

To save the changes and keep the dialog box open, click Apply. To save the changes and close the dialog box, click OK.