Issue migrating past Cesium 1.34

1. A concise explanation of the problem you're experiencing.
Due to the deprecation of old terrain provider tools, I am attempting to upgrade to the new Cesium versions to use the new terrain tools. However, when running my Visual Studio app, I get an Access Is Denied error that prevents Cesium from starting up. This error comes in at Cesium 1.35+. For lower versions 1.29-1.34, my app works.

Heres the error in Cesium 1.35:

Error: 'Access is denied.'
Code: 0
URL: file:///C:/Cesium/Build/Cesium/Cesium.js

Addtionally, on the viewer:

An error occurred while rendering. Rendering has stopped.

Error: Access is denied.

at d.load (file:///C:/Cesium/Build/Cesium/Cesium.js:521:4075)

Are you aware of a security type change that was not covered in the change log? I am currently thinking it is an issue with internet explorer and some sort of security settings.

2. A minimal code example. If you've found a bug, this helps us reproduce and repair it.

<!DOCTYPE html>
<html lang="en">
  <meta charset="utf-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no">
  <script src="../Build/Cesium/Cesium.js"></script>
      @import url(../Build/Cesium/Widgets/widgets.css);
      html, body, #cesiumContainer {
          width: 100%; height: 100%; margin: 0; padding: 0; overflow: hidden;
  <div id="cesiumContainer"></div>
    var viewer = new Cesium.Viewer('cesiumContainer');

3. Context. Why do you need to do this? We might know a better way to accomplish your goal.

Interested in generating a globe with terrain for an aircraft simulation/visualization. As of now, I don't believe there is another way to generate terrain. GoogleEarthEnterprise and other URLs that worked for versions 1.29-1.34 dont appear to be active anymore.

4. The Cesium version you're using, your operating system and browser.

Issue starts at Cesium 1.35, but can verify it happens at 1.4,1.42, and 1.53
Windows 10
Internet Explorer 11
Visual Studio 2017

Thank you for your help, it is very appreciated.

Sorry to hear you’ve having trouble. One thing that might be the issue is that if you’re not running it from a local server (like directly with the file protocol) then browsers will refuse to load assets for security reasons. Although I’m not sure why it would have been working before.

The other thing you could try is running with the CesiumUnminified version, which should give you a more descriptive error that could help us identify the issue.