No, those DLLs are not part of the .NET Framework, so repairing or re-installing the .NET Framework will not solve this problem. These DLLs are from a third party called Lassalle Technologies
Verify in your Visual Studio project's References
folder that the path to these DLLs is correct. There will be a red exclamation point or yellow triangle next to the DLL if there is an issue with it.