To update a system DSN:
Login into control panel.
Click on the ODBC DSN option, present in left frame. In the interface displayed, click on the DSN name link, which you want to update.
In the interface displayed, you can update the following information
Description: In this text box, specify the description of DSN.
File Path: In the File Path box, change the file path for database. To select the path click on the browse button. Web admin can select the database file within the \db directory of web site folder. If database driver is SQL then simply give the database name in the local SQL server.
Driver: This select box allows you the change the DSN database type.
Click on the Update button, DSN information will be updated.