Error LNK2019: unresolved external symbol "bool GIsGameAgnosticExe"

So I’ve been trying to package up my game but I always get an unresolved external symbol error. Cannot find any solutions online so any help would be appreciated.

Full log file here

Figured out the issue - this was an upgraded project and some things were missing from .Target.cs file - specifically:

Type = TargetType.Game;
DefaultBuildSettings = BuildSettingsVersion.V2;
ExtraModuleNames.AddRange( new string[] { "<GameName>" } );

Thank you! I was lacking the last line myself.