How to fix .emscripten file not found error in UE 4.14.1 Windows 10?

Here is the section of the logs…

UATHelper: Packaging (HTML5): Project.RunUnrealPak: UnrealPak Done *******
UATHelper: Packaging (HTML5): Project.CopyManifestFilesToStageDir: Copying NonUFSFiles to staging directory: E:\Temp\TappyChicken 4.14\Saved\StagedBuilds\HTML5
UATHelper: Packaging (HTML5): Project.CopyBuildToStagingDirectory: ********** STAGE COMMAND COMPLETED **********
UATHelper: Packaging (HTML5): Project.Package: ********** PACKAGE COMMAND STARTED **********
UATHelper: Packaging (HTML5): HTML5Platform.Package: Package E:\Temp\TappyChicken 4.14\TappyChicken.uproject
UATHelper: Packaging (HTML5): HTML5Platform.Package: Setting Emscripten SDK for packaging…
UATHelper: Packaging (HTML5): emcc ExitCode: 1
UATHelper: Packaging (HTML5): Program.Main: ERROR: AutomationTool terminated with exception: System.IO.FileNotFoundException: Could not find file ‘C:\Program Files (x86)\Epic Games\4.14\Engine\Intermediate\Build\HTML5.emscripten’.
UATHelper: Packaging (HTML5): File name: ‘C:\Program Files (x86)\Epic Games\4.14\Engine\Intermediate\Build\HTML5.emscripten’
UATHelper: Packaging (HTML5): at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
UATHelper: Packaging (HTML5): at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
UATHelper: Packaging (HTML5): at System.IO.FileStream…ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
UATHelper: Packaging (HTML5): at System.IO.StreamReader…ctor(String path, Encoding encoding, Boolean detectEncodingFromByteOrderMarks, Int32 bufferSize, Boolean checkHost)
UATHelper: Packaging (HTML5): at System.IO.File.InternalReadAllText(String path, Encoding encoding, Boolean checkHost)
UATHelper: Packaging (HTML5): at UnrealBuildTool.HTML5SDKInfo.SetUpEmscriptenConfigFile()
UATHelper: Packaging (HTML5): at HTML5Platform.Package(ProjectParams Params, DeploymentContext SC, Int32 WorkingCL)
UATHelper: Packaging (HTML5): at Project.Package(ProjectParams Params, Int32 WorkingCL)
UATHelper: Packaging (HTML5): at BuildCookRun.DoBuildCookRun(ProjectParams Params)
UATHelper: Packaging (HTML5): at BuildCookRun.ExecuteBuild()
UATHelper: Packaging (HTML5): at AutomationTool.BuildCommand.Execute()
UATHelper: Packaging (HTML5): at AutomationTool.Automation.Execute(List1 CommandsToExecute, CaselessDictionary1 Commands)
UATHelper: Packaging (HTML5): at AutomationTool.Automation.Process(String] Arguments)
UATHelper: Packaging (HTML5): at AutomationTool.Program.MainProc(Object Param)
UATHelper: Packaging (HTML5): at AutomationTool.InternalUtils.RunSingleInstance(Func`2 Main, Object Param)
UATHelper: Packaging (HTML5): at AutomationTool.Program.Main()
UATHelper: Packaging (HTML5): Program.Main: AutomationTool exiting with ExitCode=1 (Error_Unknown)
UATHelper: Packaging (HTML5): BUILD FAILED
PackagingResults:Error: Error Unknown Error

I followed the installation instruction months ago and I have emscripten, python, and Firefox nightly build installed.

I found out that this was causing the problem. I uninstalled .emscipten and firefox nightly build. I removed the python entries in the Path and a PYTHONHOME environment variable.

And finally HTML5 Package build was successful.