Create custom global properties for a Web Forms project from the Configuration tab page of the Project painter.

1. On the Configuration tab, select the Custom defined configuration settings option to enable the Add button.
2. Click Add.
3. Use the Add User Defined Configuration Setting dialog box to add a custom global property and a value for that property
   You cannot use a system global property name as the name for a custom global property.

When you select a custom global property in the Key and Value list box on the Configuration tab page of the Project painter, the Edit and Delete buttons become enabled. Click Edit to change the value of a custom global property. Click Delete to remove a custom global property and its value.