If the DSN (Data Source Name) for GroupWare wasn't installed properly you can follow this procedure to attempt to install it manually

On the machine hosting your database server Open Control Panel - Administrative Tools - Data (ODBC) Sources.

Choose the System DSN tab and click Add.

Select Microsoft Access Driver (*.mdb)

Click the Finish button.

Enter a name in the Data Source Name box (you will need to remember this for the configuration of Icewarp)

Click the Select button and browse to ..\Calendar\calendar.mdb file (in the Icewarp installation folder) and select it.

Click OK and the DSN is created ready for Icewarp.

Now in the Icewarp Configuration Console, choose the GroupWare menu node

Click ODBC Settings

Enter the name you chose for the DSN (see above) and click the Test Connection button.

The test should return a positive result, if it doesn't you should contact your support team.