Build and Run doesnt work for WebGl

Questions & Answers
1

When I try to build and run I’m getting this error:

FileNotFoundException: D:\webgl\Temp\StagingArea\Data\linkresult_wasm\build.wasm does not exist
    System.IO.File.Copy (System.String sourceFileName, System.String destFileName, System.Boolean overwrite) (at <1f0c1ef1ad524c38bbc5536809c46b48>:0)
    System.IO.File.Copy (System.String sourceFileName, System.String destFileName) (at <1f0c1ef1ad524c38bbc5536809c46b48>:0)
    UnityEditor.WebGL.WebGlBuildPostprocessor.AssembleOutput (UnityEditor.Modules.BuildPostProcessArgs args) (at /Users/builduser/buildslave/unity/build/PlatformDependent/WebGL/Extensions/Unity.WebGL.extensions/BuildPostprocessor.cs:644)
    UnityEditor.WebGL.WebGlBuildPostprocessor.PostProcess (UnityEditor.Modules.BuildPostProcessArgs args) (at /Users/builduser/buildslave/unity/build/PlatformDependent/WebGL/Extensions/Unity.WebGL.extensions/BuildPostprocessor.cs:934)
    UnityEditor.Modules.DefaultBuildPostprocessor.PostProcess (UnityEditor.Modules.BuildPostProcessArgs args, UnityEditor.BuildProperties& outProperties) (at C:/buildslave/unity/build/Editor/Mono/Modules/DefaultBuildPostprocessor.cs:27)
    UnityEditor.PostprocessBuildPlayer.Postprocess (UnityEditor.BuildTargetGroup targetGroup, UnityEditor.BuildTarget target, System.String installPath, System.String companyName, System.String productName, System.Int32 width, System.Int32 height, UnityEditor.BuildOptions options, UnityEditor.RuntimeClassRegistry usedClassRegistry, UnityEditor.Build.Reporting.BuildReport report) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/PostprocessBuildPlayer.cs:281)
    UnityEditor.BuildPlayerWindow:BuildPlayerAndRun()
2

Forget it.
It is an awful unity error.
I just moved the project folder to another Disk and it worked again.
this kind of bugs are horrible