App.Config Issue

 Dear all,
 Am having a problem with my app.config.Am having a class library project which needs some database information,so I added a new config file and added
 <configuration>
    <appSettings>
        <add key="connectionString"    value="Data Source=SQLSERVER;InitialCatalog=MOAQIB;UserID=test;Password=test" />
    </appSettings>
</configuration>
 During runtime when am accessing the value with configrationmanager.appsettings it raises a nullreference exception(object reference not set....)..
 Do anyone knows the solution...My class library is in C# and its called by a vb.net class library..so will that be the issue?
 
 please help..
 
regards
 Vivek

 

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