Unreal Engine Issues
Unreal Engine Issues
Available network bandwidth is too low for uncapped but slow frame rates
UE - Networking - Sep 24, 2020The networking system has a max frame rate of 120hz by default. Inside UNetConnection::Tick it computes an estimated bandwidth by using that max frame rate, the engine's max frame rate, and the actu ...
Input Actions bound to Any Key become unresponsive after mouse scroll until scrolled again
UE - Gameplay - Input - Mar 28, 2025In UE latest release (5.5 launcher version), Enhanced Input Actions mapped to "Any Key" stop responding after scrolling the mouse wheel. Specifically, scrolling either up or down disables the Any Ke ...
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 - Graphics - 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 ...
StateTree: While editing State Parameters or exposed properties of a Condition/Task, an ensure() fires when editing inputs of a Property Function bound to an array element
UE - AI - StateTree - Mar 5, 2026Consider an array property that can be edited in the StateTree editor. This can be a State Parameter or an exposed property of a Condition or Task, for example. Each element of the array can be boun ...
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 ...