# Assertion failed: NumBytes == Strings.Num()

**URL:** <https://forums.unrealengine.com/t/assertion-failed-numbytes-strings-num/489904>\
**Category:** Pipeline & Plugins\
**Tags:** unreal-engine, UE4, question\
**Created:** [October 16, 2021, 7:40pm UTC](https://forums.unrealengine.com/t/assertion-failed-numbytes-strings-num/489904 "2021-10-16T19:40:47Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![DevinSherry](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/devinsherry/32/1101099_2.png) [@DevinSherry](https://forums.unrealengine.com/u/DevinSherry)\
**Post date:** [October 17, 2021, 8:08am UTC](https://forums.unrealengine.com/t/assertion-failed-numbytes-strings-num/489904/2 "2021-10-17T08:08:20Z")

</div>

Hi,

I found this forum thread: [Unreal Engine 5 crashes on Start up - #2 by eonridr](https://forums.unrealengine.com/t/unreal-engine-5-crashes-on-start-up/232776/2). It is originally from an Unreal Engine 5 issue, but a few comments into the thread state that the proposed fix works for 4.26 and 4.27. Here is the answer from user Varxon:

**This error comes from a corrupted CachedAssetRegistry.bin file. Reinstalling it does not fix the file.  
To fix this, you are going to want to go to file location C:\Users\username\AppData\Local\UnrealEngine\5.0\Intermediate - Locate the file named CachedAssetRegistry.bin and delete it. After deleting it, you should be able to launch**

Obviously, just adjust the directory to match where this file will be located. I hope this works, and good luck 🙂

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