[Critical] UEFN Crashing regularly since 41.00 with excessive memory usage

GraemeBB · June 9, 2026, 12:40am

Summary

Nothing has changed in my workflow or settings outside of updating to 41.00 and an out of video memory error comes up and UEFN crashes (or sometimes Fortnite). I have a 16GB 4090 and an i9 with 32GB of memory. I’ve heard quite a few people are having this issue so I’m posting a bug finally.

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Stability

Steps to Reproduce

Just build stuff

Expected Result

UEFN should run forever like it did before 41.00

Observed Result

UEFN crashes every third or so push of a map test

Platform(s)

PC

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GraemeBB · June 9, 2026, 12:47am

Here’s a new error

Fatal error: [File:Z:\UEVFS\Root\Engine\Source\Runtime\Core\Private\GenericPlatform\GenericPlatformMemory.cpp] [Line: 300]
Ran out of memory allocating 3259194 (3.1 MiB) bytes with alignment 1. Last error msg: The paging file is too small for this operation to complete..

Bug-Reporter · June 9, 2026, 12:54am

FORT-1114647 has been created and its status is ‘Unconfirmed’. This is now in a queue to be reproduced and confirmed.

GraemeBB · June 9, 2026, 1:09am

here’s a cool error message it just threw up before crashing

OffTheX-Lee · June 9, 2026, 1:24am

I ran into many times this weekend

GraemeBB · June 9, 2026, 1:32am

Here’s one more screenshot of what shows up in the logs when I start a session.

ozycreates · June 9, 2026, 5:30am

I noticed in my particular case crashes happen while vs code is open, it causes UEFN to consume way too much memory

ozycreates · June 9, 2026, 7:00am

Also, after crashing even ONCE I can’t launch session ever again. I have to restart my PC.

Flak · June 9, 2026, 10:34am

Thanks for the report, getting this to the team.

Flak · June 9, 2026, 10:37am

@GraemeBB and anyone else this is happening to, could we please get your logs?