# Connection to Cesium ion fails **URL:** \ **Category:** Cesium for Unreal\ **Created:** [March 28, 2025, 12:08pm UTC](https://community.cesium.com/t/connection-to-cesium-ion-fails/39649 "2025-03-28T12:08:35Z")\ **Posts on this page:** 1\ **Showing post:** 4
**Author:** ![Kevin\_Ring](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/kevin_ring/32/2003_2.png) [@Kevin\_Ring](https://community.cesium.com/u/Kevin_Ring)\ **Post date:** [April 11, 2025, 9:17am UTC](https://community.cesium.com/t/connection-to-cesium-ion-fails/39649/4 "2025-04-11T09:17:28Z")
Hi @A.Hardy, That’s a strange error, and we’re not sure what to make of it. It’s a bit of a long shot, but you might try following the instructions here on the problematic machine and see if it helps: > [@KNOWN ISSUE: Tilesets not loading in packaged Unreal apps](https://community.cesium.com/t/known-issue-tilesets-not-loading-in-packaged-unreal-apps/36043/24): > > I’m slowing learning a bit more here… From what I can gather piecing together information from various non-authoritative sources, Windows has a mechanism where it automatically downloads new certificate authority certificates from Windows Update on-the-fly as they’re needed. However, it can only do this for applications that use the “proper” Windows APIs to manage certificates. Presumably, this does not include Unreal Engine. Therefore, if you’re running on a system where the “Starfield Servic… Another possibility is that you network and/or Zscaler requires an HTTP proxy, particularly for POST requests. Unreal Engine does _not_ automatically use the proxy configured for Windows. If this is the problem, some users have been able to solve it as described here: > [@Error connecting Cesium to Unreal](https://community.cesium.com/t/error-connecting-cesium-to-unreal/12953/7): > > Hi @Rookie_Chris, Cesium for Unreal uses Unreal Engine’s FHttpModule to do HTTP requests. It looks like that does have proxy support, accessible from the C++ API. See SetProxyAddress: I was surprised it doesn’t appear to be configurable in an .ini file or anything like that, though. If your connection requires a proxy, I would expect tile requests to fail, too. When you open the Samples project, do you get a globe at all? Or maybe your network requires a proxy for POST requests but not GET r… --- _[View the full topic](https://community.cesium.com/t/connection-to-cesium-ion-fails/39649)._