Text Mesh Pro Error (2019)

I updated my project to 2019.1 today and after updating was met with a huge list of errors. They are all related to Text Mesh Pro. I have tried reinstalling TMP but this did not solve any issues. The issues go away if I uninstall TMP, but I have it implemented into a couple of systems so I would rather keep it if possible.

This is the error being thrown:

C:/Users/jamie/Documents/Unity Games/Wrong_Turn_II/Library/PackageCache/com.unity.textmeshpro@2.0.0/Scripts/Runtime/TMPro_UGUI_Private.cs(1865,73): error CS1644: Feature `out variable declaration' cannot be used because it is not part of the C# 4.0 language specification

Any help is appreciated thank you

Switch your player settings’ Scripting Runtime version to be using .Net 4.x

I have the exact same issue after installing and upgrading a project to Unity 2019 today,

There is no “Scripting Runtime version” at 2019.2.12f1. But I solved this problem with change “Edit > Project Settings > Player > Other Settings > Api compatibility Level” to .NET 4.x.

The problem will continue due to a protection program such as avast, so it must be stopped until the tool is installed