# UEFN 42.20: Python cleanup crashes and confirmed native callable size mismatch

**URL:** <https://forums.unrealengine.com/t/uefn-42-20-python-cleanup-crashes-and-confirmed-native-callable-size-mismatch/2833673>\
**Category:** Issues and Bug Reporting\
**Tags:** open, fortnite-creative, unreal-editor-for-fortnite, fortnite\
**Created:** [September 23, 2026, 4:53pm UTC](https://forums.unrealengine.com/t/uefn-42-20-python-cleanup-crashes-and-confirmed-native-callable-size-mismatch/2833673 "2026-09-23T16:53:08Z")\
**Posts on this page:** 1\
**Showing post:** 3

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**Author:** ![rhyan.smith](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/rhyan.smith/32/1218554_2.png) [@rhyan.smith](https://forums.unrealengine.com/u/rhyan.smith)\
**Post date:** [September 24, 2026, 2:10pm UTC](https://forums.unrealengine.com/t/uefn-42-20-python-cleanup-crashes-and-confirmed-native-callable-size-mismatch/2833673/3 "2026-09-24T14:10:43Z")

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Hi, thanks for reporting this to us.

Please could you provide us with your logs

How to get logs:

> [@How to get your Fortnite logs](https://forums.unrealengine.com/t/how-to-get-your-fortnite-logs/682382):
>
> At times, we will ask you to send us your logs when you’re having an issue in UEFN. Here is how to do that: UEFN Logs Exit Fortnite. Click on Start or press the Windows Key + R. Type \AppData\Local\UnrealEditorFortnite\Saved\Logs and press Enter. Zip your Logs folder and attach the zip file to your reply. To find UEFN Logs while working in UEFN: Click “Output Log” at the bottom of the window. Click on “Setting” at the top right of the window Click “Open Source Location” Zip your Logs folder…

Feel free to [privately message me](https://forums.unrealengine.com/new-message?username=rhyan.smith) the logs

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