# Unreal Engine Crash When Dragging Mesh To The Viewport

**URL:** <https://forums.unrealengine.com/t/unreal-engine-crash-when-dragging-mesh-to-the-viewport/1169394>\
**Category:** Feedback & Requests\
**Tags:** unreal-engine\
**Created:** [May 18, 2023, 4:01am UTC](https://forums.unrealengine.com/t/unreal-engine-crash-when-dragging-mesh-to-the-viewport/1169394 "2023-05-18T04:01:16Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![BouvToTheMaxi](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@BouvToTheMaxi](https://forums.unrealengine.com/u/BouvToTheMaxi)\
**Post date:** [May 18, 2023, 4:31pm UTC](https://forums.unrealengine.com/t/unreal-engine-crash-when-dragging-mesh-to-the-viewport/1169394/2 "2023-05-18T16:31:07Z")

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> [@Assertion failed: MacAddress.Num() == 6](https://forums.unrealengine.com/t/assertion-failed-macaddress-num-6/511376):
>
> I’m running UE 5.0.0 (Preview 2) on Windows 10. The editor crashes when trying to open my World Partition level. The issue happens after I close Unreal and try to reopen. It will continue to crash with the same error until I restart my computer. After restarting, it will work properly until I have to close and reopen again. Any suggestions on how to fix this? Here’s the traceback from the crash window: LoginId: \*\*\* EpicAccountId: \*\*\* Assertion failed: MacAddress.Num() == 6 [File:D:\build\+…

“So as it turns out, MacAddress is literally referring to your networks on your PC. 1. I had a ton of disconnected virtual network adapters piled up, so I disabled them all, and now I can place actors in my levels without it crashing.” it helped me

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