Quick answer: Unreal SpawnActorFromClass returning null on dedicated server? Class might be flagged client-only via NeedsLoadForClient - check NeedsLoadForServer is true.
Server tries to spawn a UI-related actor for a server-side mock. Returns null.
Check class flags
UClass settings > Needs Load for Server. If unchecked, the class doesn't exist server-side. Either check it or refactor the actor.
Avoid mixing UI in gameplay
UI-tagged classes should be client-only. If the server needs UI-like data, extract a server-side data class.
Audit class flags
Window > Class Viewer > Filter by 'NotPlaceableInServer'. Catches misconfigured classes before runtime null.
“Class flags split your codebase by network role. Spawn failures surface the splits.”
Document class-flag conventions in your engineering wiki. New contributors need to know which classes are which.