why are the show this error in my project please help me ...

Question

 </buildProviders> Line 136:            <folderLevelBuildProviders> Line 137:                <add name="DataServiceBuildProvider" type="System.Data.Services.BuildProvider.DataServiceBuildProvider, System.Data.Services.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" /> Line 138:            </folderLevelBuildProviders> Line 139:            <expressionBuilders>