# Unable To Play: Failed to upload source files 

**URL:** <https://forums.unrealengine.com/t/unable-to-play-failed-to-upload-source-files/2728802>\
**Category:** Issues and Bug Reporting\
**Tags:** unreal-engine, unreal-editor-for-fortnite, bug-report, editor\
**Created:** [June 15, 2026, 2:27pm UTC](https://forums.unrealengine.com/t/unable-to-play-failed-to-upload-source-files/2728802 "2026-06-15T14:27:22Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![Jimbohalo10](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/jimbohalo10/32/961440_2.png) [@Jimbohalo10](https://forums.unrealengine.com/u/Jimbohalo10)\
**Post date:** [June 15, 2026, 6:40pm UTC](https://forums.unrealengine.com/t/unable-to-play-failed-to-upload-source-files/2728802/2 "2026-06-15T18:40:14Z")

</div>

hi @Funsockman

There is a know problem which can be found in the log file that is stopping for lori uploading

[v41.00 Known Issues & Pre-Release Updates - General / Issues and Bug Reporting - Epic Developer Community Forums](https://forums.unrealengine.com/t/v41-00-known-issues-pre-release-updates/2726053/4)

- If you do, please clear the following directory and try again.

`%LOCALAPPDATA%/UnrealEditorFortnite/Intermediate/ValkyrieUploadTemp`

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