It seems, that the 4.0 Assembly loader will not load/accept the Telerik.Reporting.dll, because this dll is targeted to 2.0 !
the Telerik.reporting.dll usally works, but when i need to add some AssemblyReferences..., i must use the .Net Configuration system. -> without the <configSections> block, it works!
<configuration>
<configSections> <section name="Telerik.Reporting" type="Telerik.Reporting.Configuration.ReportingConfigurationSection, Telerik.Reporting" allowLocation="true" allowDefinition="Everywhere"/> </configSections> …
<Telerik.Reporting>
<AssemblyReferences>
....
</configuration>