"Assertion failed: NumberOfFreeBits >= 0" on clients that attempt to connect to a server with the -NoPacketHandler option

UE - Networking - Oct 6, 2020

With the rework of IP address resolution in 4.25, this assert now occurs. When no packet handler is used, UPendingNetGame::InitNetDriver calls SendInitialJoin() immediately, before async address res ...

Deferring Blueprint CDO construction at load time is leading to some data loss.

UE - Gameplay - Blueprint - Jan 27, 2023

Various licensees are reporting data loss on load due to the change that was made for [Link Removed] in which we now defer Blueprint CDO construction on load until the finalization phase. This issu ...

[CrashReport] ULevel::GetWorldSettings() - UMaterialInstanceThumbnailRenderer::Draw

Tools - Aug 29, 2017

This is a common assertion that has occurred since at least 4.14 and affected nearly 100 users. The callstack is similar to [Link Removed], which was marked fixed for 4.14. User DescriptionsUndoi ...

LogAudioMixer warning results in a decrease of performance

UE - Audio - May 21, 2020

Unable to reproduce. User believes it is directly related to the speaker they are using when it goes into standby mode. If they unplug the speaker, everything runs okay.  After receiving the warning ...

Changing the name of a native component results in a blank details panel

UE - Gameplay - Components - May 7, 2021

Much like [Link Removed] (which I'm backing down on my by design claim), there is an issue where if you previously referenced a component that no longer exists, the correct instanced subobject is lo ...

UFE: Can't delete custom launch profiles

UE - Editor - UI Systems - Jul 26, 2023

The confirmation message will fails spawning with the following messages in the log:  [2023.07.25-20.04.01:038][  0]LogWindows: Error: Failed to create dialog. The specified resource type cannot be ...

Descriptions for vis log shapes in the Rewind Debugger are misaligned

UE - AI - Debugging - Mar 25, 2025

When recording shape information, descriptions are offset from the shape. Licensee Message - I noticed that the capsule vis log description labels were not lining up after replaying the recording ...

Interface function has the incorrect pin type if referencing self

UE - Gameplay - Blueprint - Sep 1, 2015

Interface function has the incorrect pin type if referencing self User Description: I have an interface that requires an array of its own interfaces as output. I have that array of interface as a ...

[CrashReport] UE4Editor_Core!rml::internal::ExtMemoryPool::initTLS()

UE - Gameplay - Blueprint - Aug 15, 2017

This is a trending crash coming out of the 4.17.0 release. Users have not provided any descriptions of their actions when the crash occurred. The callstack shares some similarities to an older 4.14 ...

Grandchild actor with IsEditorOnly enabled is duplicated during save the level.

UE - Gameplay - Components - Dec 6, 2019

IsEditorOnly is not reflected in grandchild actor when parent/child/grandchild are constructed with ChildActorComponent. This causes the issue that actor will increase incorrect when save the level. ...