# CRITICAL - UEFN session not start in Fortnite (map testing not possible !!!) **URL:** \ **Category:** Issues and Bug Reporting\ **Tags:** testing, unreal-editor-for-fortnite, bug-report, fortnite\ **Created:** [October 24, 2024, 12:38pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218 "2024-10-24T12:38:44Z")\ **Posts on this page:** 18\ **Page:** 2
**Author:** ![Karo-Bube](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/karo-bube/32/1203551_2.png) [@Karo-Bube](https://forums.unrealengine.com/u/Karo-Bube)\ **Post date:** [October 28, 2024, 5:48pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/21 "2024-10-28T17:48:11Z")
@Flak I don’t know what you mean. “Help”-\>“Report a problem” in UEFN? Then I land on that forum page 🫤 Can’t do anything with the log-file I posted? ---
**Author:** ![Flak](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/flak/32/769441_2.png) [@Flak](https://forums.unrealengine.com/u/Flak)\ **Post date:** [October 31, 2024, 10:26am UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/22 "2024-10-31T10:26:12Z")
It should have also submitted your full logs to us but it appears the process may have stopped somewhere. Could you please zip up your log folder and send it to me either in the post or via DM? ---
**Author:** ![Flak](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/flak/32/769441_2.png) [@Flak](https://forums.unrealengine.com/u/Flak)\ **Post date:** [October 31, 2024, 10:49am UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/24 "2024-10-31T10:49:56Z")
OK, it looks like some of your post was deleted. When you start a new post from inside of UEFN, please fill out all of the information and do not delete any of your post. It helps us to find your information on the server so we can troubleshoot. ---
**Author:** ![Karo-Bube](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/karo-bube/32/1203551_2.png) [@Karo-Bube](https://forums.unrealengine.com/u/Karo-Bube)\ **Post date:** [October 31, 2024, 12:25pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/25 "2024-10-31T12:25:16Z")
> [@Flak](#): > > Could you please zip up your log folder and send it to me either in the post or via DM? I posted the complete log history after clicking on “Start session” in UEFN on October 25th (Look further up). That’s all I have!? ---
**Author:** ![davidpkami](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/davidpkami/32/1040403_2.png) [@davidpkami](https://forums.unrealengine.com/u/davidpkami)\ **Post date:** [November 1, 2024, 12:59pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/26 "2024-11-01T12:59:09Z")
Same problem with us. Can not test anything. The game crashes when trying to join a test sesion (UEFN Launch, not private test code). Imposible to test the basic OnJoin functions. Trying to join a test on Switch: ![IMG_3591](https://d3kjluh73b9h9o.cloudfront.net/original/4X/a/d/5/ad5b2d062689f838657545b001ba9a17146fdb6d.jpeg) **Game crash** Trying to join a test on IOs: ![IMG_3590](https://d3kjluh73b9h9o.cloudfront.net/original/4X/a/b/b/abb3cbd9c0da32470dea51d04d56c72a76758426.jpeg) **Infinite load screen** Trying to join a test on Android: Game crash. Go back to Android main menu ---
**Author:** ![MIguelFaro](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@MIguelFaro](https://forums.unrealengine.com/u/MIguelFaro)\ **Post date:** [November 1, 2024, 6:28pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/27 "2024-11-01T18:28:28Z")
Hi David @davidpkami , Im having the exact same issue as you I made a post here [CRITIAL- Nintendo Switch Crashing (or not) in exact same island depending if its an editor\_session/private\_code/public\_code](https://forums.unrealengine.com/t/critial-nintendo-switch-crashing-or-not-in-exact-same-island-depending-if-its-an-editor-session-private-code-public-code/2073164) Did you start working on your project a long time ago? From similar reports it seems this issue only happens in projects that have been in development for multiple months ---
**Author:** ![davidpkami](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/davidpkami/32/1040403_2.png) [@davidpkami](https://forums.unrealengine.com/u/davidpkami)\ **Post date:** [November 2, 2024, 10:36am UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/28 "2024-11-02T10:36:06Z")
Yes, then project has more than 4 months ---
**Author:** ![MIguelFaro](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@MIguelFaro](https://forums.unrealengine.com/u/MIguelFaro)\ **Post date:** [November 2, 2024, 12:46pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/29 "2024-11-02T12:46:36Z")
It seems like some time during the last fortnite season epic introduced this render-related setting in the island settings. I did some research and found absolutely nothing about this. If you go to any material there’s also a similar new setting there. I turned them all off but still have crashes, exact same behaviour ![screenshoot](https://d3kjluh73b9h9o.cloudfront.net/original/4X/1/4/2/142c35220f3fa3742dc04e281f8e6a483ececab8.png) ---
**Author:** ![Flak](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/flak/32/769441_2.png) [@Flak](https://forums.unrealengine.com/u/Flak)\ **Post date:** [November 4, 2024, 1:35pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/30 "2024-11-04T13:35:31Z")
Could everyone please reproduce the issue and then zip up your log folder and post it here? If you’re not comfortable with that you can send it to me in a DM. Thank you! ---
**Author:** ![Karo-Bube](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/karo-bube/32/1203551_2.png) [@Karo-Bube](https://forums.unrealengine.com/u/Karo-Bube)\ **Post date:** [November 4, 2024, 3:14pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/31 "2024-11-04T15:14:00Z")
Hi @Flak, here is my log from starting UEFN until demolition in UEFN… [Karo-Bube\_logs\_04.11.2024.zip](https://forums.unrealengine.com/uploads/short-url/aiB5EMuUxySP7wsPUh421BA2DxO.zip) (188.2 KB) ---
**Author:** ![MIguelFaro](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@MIguelFaro](https://forums.unrealengine.com/u/MIguelFaro)\ **Post date:** [November 4, 2024, 5:26pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/32 "2024-11-04T17:26:27Z")
Hi @Flak I seem to be having the same issue that @davidpkami mentioned above I made a post about it using the UEFN help button, the logs should be there for you > [@CRITIAL- Nintendo Switch Crashing (or not) in exact same island depending if its an editor\_session/private\_code/public\_code](https://forums.unrealengine.com/t/critial-nintendo-switch-crashing-or-not-in-exact-same-island-depending-if-its-an-editor-session-private-code-public-code/2073164): > > Summary This post will describe all the weird general behaviors of this issue, as well as some workarounds used to get the Switch into the project, at the end of this post I’m sure it will be clear that this is an issue on Epic’s side. Nintendo Switch and low end android devices are crashing every time they join our UEFN session. But if at ANY time I make a private code version of the island, I’m able to join with the Nintendo Switch and Android with NO ISSUES AT ALL. This project is almost c… ---
**Author:** ![Flak](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/flak/32/769441_2.png) [@Flak](https://forums.unrealengine.com/u/Flak)\ **Post date:** [November 5, 2024, 3:11pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/33 "2024-11-05T15:11:33Z")
@Karo-Bube - could you get us this too? C:\Users\\AppData\Local\FortniteGame\Saved\Logs\FortniteGame.log ---
**Author:** ![Karo-Bube](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/karo-bube/32/1203551_2.png) [@Karo-Bube](https://forums.unrealengine.com/u/Karo-Bube)\ **Post date:** [November 5, 2024, 4:23pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/34 "2024-11-05T16:23:06Z")
[Karo-Bube\_FortniteGame.zip](https://forums.unrealengine.com/uploads/short-url/3vhaE7tD0uXqTa6OzMEvquQHIm4.zip) (617.5 KB) ---
**Author:** ![Flak](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/flak/32/769441_2.png) [@Flak](https://forums.unrealengine.com/u/Flak)\ **Post date:** [November 7, 2024, 3:10pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/35 "2024-11-07T15:10:41Z")
Thank you so much! ---
**Author:** ![Karo-Bube](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/karo-bube/32/1203551_2.png) [@Karo-Bube](https://forums.unrealengine.com/u/Karo-Bube)\ **Post date:** [November 7, 2024, 3:31pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/36 "2024-11-07T15:31:30Z")
With pleasure. I hope this helps your colleagues to localize the problem and fix it. ---
**Author:** ![Flak](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/flak/32/769441_2.png) [@Flak](https://forums.unrealengine.com/u/Flak)\ **Post date:** [November 8, 2024, 5:48pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/37 "2024-11-08T17:48:13Z")
The others i this thread seem to have another issue than you and we’re not seeing any other reports of what you’re seeing. We’re checking into it though. Ticket for this issue is FORT-818917 ---
**Author:** ![Karo-Bube](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/karo-bube/32/1203551_2.png) [@Karo-Bube](https://forums.unrealengine.com/u/Karo-Bube)\ **Post date:** [November 8, 2024, 6:21pm UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/38 "2024-11-08T18:21:32Z")
Thank you. A note for you at this point… I now have a “reasonably working” workaround…: 1.) I start Fortnite first before I start UEFN 2.) When Fortnite has loaded completely, I wait a few minutes and then start UEFN (so I don’t get the login error) 3.) When my UEFN project is fully loaded, I start the editing session **IN FORTNITE** (I find this under “last played”) 4.) I wait until the loading screen of the editing session appears in Fortnite and then connect the editing session from UEFN at the same time I usually have success when I go through points 3 and 4 about two to five times. Well, it’s not a good situation, of course, but I’m glad that I can test at all (if the “workaround” works). That’s why I hope you can manage it… → In my opinion, a too early timeout is responsible here, which then breaks the connection in UEFN (shortly?) before the connection would be established! (Maybe this will help you and thanks for your efforts) ---
**Author:** ![Flak](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/flak/32/769441_2.png) [@Flak](https://forums.unrealengine.com/u/Flak)\ **Post date:** [November 12, 2024, 10:51am UTC](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218/39 "2024-11-12T10:51:51Z")
We appreciate it! I’ll pass this along. [Previous page](https://forums.unrealengine.com/t/critical-uefn-session-not-start-in-fortnite-map-testing-not-possible/2085218.md?page=1)