2019.1.1f1 Update

Hi, i just recently updated to the new version of Unity and I’ve gotten 51 error messages saying “Feature ‘out variable declaration’ cannot be used because it is not part of the C# 4.0 language specification”. I then tried to downgrade back to Unit 2018 unity but i get error messages saying certain dependencies cannot be loaded. As a result I’ve got a game project that I have been working on for the past two years that no longer runs or can be built. Is anyone else having this issue? Has anyone found a solution to it? Help would be greatly appreciated. Thank you.

I’m not going to harp on the “back up your project before you upgrade your assets or Unity version”, a lesson already learned.

BTW, I recently upgraded a project to 2019.1.0f1 and found all sorts of little bugs that were just getting annoying. I downgraded my project and yes, things (such as the package manager assets) constantly complained. I did not do a backup either, but I did not have as much invested. However, this was my strategy to save what work I did do:

  • in my project’s folder, I remember the hidden folders, folders, and files that Unity created (this included .asset files, the Package and Library folder, Visual Studio solution and .vs folder, etc.);
  • alternately (and this was an afterthought), I could have probably just exported all of my assets into a Package file that could have been re-imported into an older version; however,
  • I opened the project from the Unity Hub where I had removed all of the newer version files and let it do its thing. It didn’t complain, but I had to make sure I pulled in all the packages and assets that were needed.

You can back up what you have and give this a try.

Note: I did notice in my project that I did have to re-bake my NavMesh, so there are probably things like NavMeshes and Lighting that have to be re-processed when re-including your assets in a downgraded project.

[Edit: Corrected list and added extra info.]