Unreal Engine Issues
Unreal Engine Issues
Actors in sublevels do not replicate to Clients after Seamless ServerTravel
UE - Networking - Dec 9, 2015Actors in sublevels do not replicate to Clients after Seamless ServerTravel. The user reporting this noted that "[...] UNetDriver::IsLevelInitializedForActor() keeps returning false even when the ac ...
Niagara Data Interface "Errors and Warning" section on Module Details not updating when error messages change
UE - Niagara - Aug 14, 2025This is a regression: it worked correctly up to UE 5.5, but not in 5.6 or mainline latest. Possibly caused by CL 40093049. Class UNiagaraDataInterface provides virtual method GetFeedback(), which a ...
NavLink Proxy CHILD ACTOR stops working in a Packaged and Standalone game
UE - AI - Oct 5, 2017NavLink Proxy CHILD ACTOR stops working in a Packaged and Standalone game. Works as expected in PIE. Licensee Description: Force Rebuild on Load is not called and the nav links as child actors do ...
Missing UV Clamping or Clear in SunAlphaPS_Mobile
UE - Platform - Mobile - Nov 13, 2025In: void SunAlphaPS_Mobile( float2 InUVs[8] : TEXCOORD0, in FStereoPSInput StereoInput, out HALF_TYPE OutColor : SV_Target0 ) { OutColor = SunUnBias(SunShaftAndDofTexture.Sample(SunShaftAndDo ...
Niagara - When Interpolated Spawning is disabled, the first frame of each particle unexpectedly does not take into account the Particle Update stage
UE - Niagara - Feb 28, 2025Foreword: Even if the behavior described here is by design, it is rarely (if ever) expected or desired. This was discussed and agreed to be treated as a bug. Explanation below. When interpolated sp ...
Users Unable to create C++ Projects
UE - Foundation - Core - Mar 6, 20152nd AH post with the same issue: https://answers.unrealengine.com/questions/183441/cant-load-c-projects.html Multiple people have reported not being able to create a C++ project. Creating a Bluepr ...
Niagara Scalability Crash When Processing Significance
UE - Niagara - Jun 4, 2025Method FNiagaraScalabilityManager::ProcessSignificance() iterates on indices from Context.SignificanceIndices and uses them to access the State and ManagedComponents arrays. It can then decide to cr ...
When duplicating multiple actors with alt+drag, Translation/Rotation widget goes to incorrect coordinate space
UE - Editor - Workflow Systems - Mar 4, 2024Note: This bug has been observed in all tested engine versions, from UE 4.24 to UE 5.3 and in ue-main. When shift+selecting multiple actors in the Level Editor, the currently-active transformation ...
Incorrect config property serialization for UStructs used as TMap keys or contained in a TSet with a single value. Diffs taken from default-value of each member type, instead of from default-value of the struct
UE - CoreTech - Nov 18, 2024Consider a UStruct with some basic type members, each one with a default value specified in the struct. Also consider a TSet or TMap with that struct as keys, used inside a UObject as a UProperty an ...
Cannot select child anim BPs for use in linked anim layers
UE - Anim - Runtime - Jul 15, 2021From UDN: [Link Removed] Unable to set a Child ABP with inherited interface to a Linked Animation Layer Instance Class. I have a ABP_Biped which is our main ABP. I have the locomotion (idle+straf ...