You get this error when running your application:
Could not load type System.DateTimeOffset from assembly mscorlib, Version=2.0.0.0, Culture=neutral,
System.DateTimeOffset is new to .NET Framework 3.5 SP1, 3.0 SP1 and 2.0 SP1. Make sure your system has the correct service pack installed.
http://social.msdn.microsoft.com/Forums/en-US/sqltools/thread/a79d96ba-398a-46c1-aeee-353791a65e43/
Part IX: Troubleshooting Applications
Application Runs But No Data is Displayed