In Microsoft SharePoint products, restoration of the configuration database is not supported using the built in backup and restore functionality. In order to restore the configuration database you must use separate steps and prescriptive guidance.
We do not support restoration of the configuration database in SharePoint products using the built in backup and restore functionality.
If you restore the configuration database, data in the configuration database will not be synchronized with data in other SharePoint databases. If this data is not synchronized, users may experience various random errors.
For example, a Windows SharePoint Services 3.0
content database may contain data about a newer site. If the configuration
database does not contain information about this site, the site is orphaned.
In order to restore the configuration database, you have to use manual steps. You cannot use the built-in backup and restore functionality. This guidance is provided in documentation on the following Microsoft TechNet Web sites: