UEFN "launch session" cannot load map into Fortnite to playtest

Summary

I am having a few issues all revolving around trying to playtest my custom maps I make in UEFN. Simply put, I go to press the button “launch session” in the UEFN editor while my map is opened in the editor, and Fortnite tries to load it and fails.

For this instance right now, I have my project opened in the editor, I press “launch session” and Fortnite starts to open. Usually Fortnite takes a good couple to several minutes to load for me in general. After maybe a minute of the Fortnite loading/starting screen, I receive these two error messages (images attached). Normally at this point, my computer bluescreen crashes (this time it didn’t and it allowed me to screenshot the error code).

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Other

Steps to Reproduce

  • Start UEFN editor and open up the project, allow it to load
  • Then press “launch session” button and wait for Fortnite to open

Expected Result

  • Fortnite opens and automatically loads into the custom map for testing

Observed Result

  • Crashes on trying to start Fortnite during Fortnite loading screen

Platform(s)

PC laptop, Windows 10, Asus Zephyrus GM501G
Below are copy-pasted stats from “About PC”

Edition Windows 10 Pro
Version 22H2
Installed on ‎10/‎14/‎2021
OS build 19045.5198
Experience Windows Feature Experience Pack 1000.19060.1000.0

Device name -------
Processor Intel(R) Core™ i7-8750H CPU @ 2.20GHz 2.21 GHz
Installed RAM 16.0 GB (15.9 GB usable)
Device ID ------
Product ID ------
System type 64-bit operating system, x64-based processor
Pen and touch Pen support

UEFN info:
Version: 5.6.0-38504598+++Fortnite+Release-33.00

Island Code

not published yet except for private test versions

Upload an image


Additional Notes

  • I have tried to work around the crashes in loading Fortnite by opening Fortnite separately. Fortnite doesn’t always open if UEFN is already open / running. I am unable to get the custom map loaded into Fortnite in this way too if Fortnite does open while UEFN is open.

  • In other cases, UEFN “launch session” button may load Fortnite successfully (I see the Fortnite main lobby) but my map does not load for playtesting. In that case, Fortnite will look like it’s loading into a game with a loading screen, take some time, then quit loading and go back to the main menu lobby. It won’t show the custom map in Fortnite before it goes back to lobby.

  • Trying to use the “UEFN session” button in Fortnite’s recently played history itself will let me press “play” and after a few seconds return with something like “matchmaking error 3”

  • I can’t start Fortnite sometimes if UEFN is already running. In the Epic Games Launcher, both Fortnite and UEFN show as “running”

  • The only successful workaround I have for testing a map from UEFN right now is to use in UEFN editor: Project > “Upload to private version” and then use that generated island code to play test my custom map. This works but is a bit tedious for trying out and experimenting with small changes each time.

  • I now run the Epic Games Launcher in administrator mode from another post on here, but my issue happens after doing that still.

Strange, I just had UEFN open for a bit after writing this post, then I tried “launch session” again and suddenly it is currently working for the first time since using UEFN… I will update more if I find out what is causing it to work / not work differently. The only difference I can say right now is that I kept UEFN open, tried opening Fortnite separately (which didn’t open or start) and then I tried the same thing “launch session” button some time after that.

Can you try it plugged into router instead of wifi

If your using World Partitions, make sure you have freshly built HLODs before you launch.

I will try that sometime, thanks for the reply!
Also I built the HLODS after finishing my base island layout

1 Like

Apologies, I thought I had the ethernet to USB c connector I needed to connect an ethernet cable to my laptop but apparently I lost that some time ago. So I can’t test a physical connection to the router right now.

That said, I did bring my laptop from its usual place upstairs to the living room with the router, still connected to wifi, and the UEFN editor and Fortnite both seemed to load correctly (though it still takes some time). I was able to load into the UEFN editor and then launch session and load the custom map in Fortnite in one try.

I am having more success now with getting into the custom map overall when I try a couple times even when I’m upstairs. I used to not be able to at all, so at least I can test things now.

My ping upstairs is usually not great for gaming but I make do lol. Maybe it is something with the timeout combined with my ping being higher upstairs that causes this.

1 Like