...
<DNL:DbNetGrid 
     ID="DbNetGrid1" 
     runat="server" 
     ConnectionString="SamplesDatabase" 
     FromPart="Suppliers"
 </DNL:DbNetGrid>
 ...
 web.config
 ...
 <?xml version="1.0"?>
 <configuration>
     <connectionStrings>
         ...
         <add name="SamplesDatabase" connectionString="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=~/App_Data/DbNetSuiteVS.mdb"/>
         ...
     </connectionStrings>
     ...
 </configuration>
 ...