title: CS1617 error message when building MonoDevelop 7.6 with Visual Studio 2017
body: <p>I have an error message when building under Windows 10 and Visual Studio 2017 Team explorer.</p>
  <p>&quot;CSC : error CS1617: Option non valide '8.0' pour /langversion. Utilisez '/langversion:?' pour lister les valeurs prises en charge.&quot;</p>
  <p>I use the winbuild bat file. I tried to build from VS also. I followed the instructions on the page <a href="https://www.monodevelop.com/developers/building-monodevelop/" rel="nofollow noreferrer">https://www.monodevelop.com/developers/building-monodevelop/</a></p>