Please help, cannot package because of errors

Hi all,
I have built my project successfully but now i have to package it and it wont work. Not sure what i have missed but i have checked all blueprints and they compile fine. Also deleted my saved and intermediate folders and still to no avail.
Would really appreciate any help on this.
Many Thanks
Please see output log error here:

UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: begin: stack for UAT
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: === Critical error: ===
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error:
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: Fatal error: [File:D:\Build++UE4\Sync\Engine\Source\Runtime\Core\Public\Serialization/MemoryWriter.h] [Line: 42]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: FMemoryWriter does not support data larger than 2GB. Archive name: None.
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error:
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error:
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffedc29a388 KERNELBASE.dll!UnknownFunction []
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe972dcd1a UE4Editor-Core.dll!FWindowsErrorOutputDevice::Serialize() [d:\build++ue4\sync\engine\source\runtime\core\private\windows\windowserroroutputdevice.cpp:63]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe970ba967 UE4Editor-Core.dll!FOutputDevice::LogfImpl() [d:\build++ue4\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:71]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe96ff0df7 UE4Editor-Core.dll!FDebug::AssertFailed() [d:\build++ue4\sync\engine\source\runtime\core\private\misc\assertionmacros.cpp:417]
PackagingResults: Error: begin: stack for UAT
PackagingResults: Error: === Critical error: ===
PackagingResults: Error: Fatal error: [File:D:\Build++UE4\Sync\Engine\Source\Runtime\Core\Public\Serialization/MemoryWriter.h] [Line: 42]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe968429f3 UE4Editor-CoreUObject.dll!FMemoryWriter::Serialize() [d:\build++ue4\sync\engine\source\runtime\core\public\serialization\memorywriter.h:42]
PackagingResults: Error: FMemoryWriter does not support data larger than 2GB. Archive name: None.
PackagingResults: Error: [Callstack] 0x00007ffedc29a388 KERNELBASE.dll!UnknownFunction []
PackagingResults: Error: [Callstack] 0x00007ffe972dcd1a UE4Editor-Core.dll!FWindowsErrorOutputDevice::Serialize() [d:\build++ue4\sync\engine\source\runtime\core\private\windows\windowserroroutputdevice.cpp:63]
PackagingResults: Error: [Callstack] 0x00007ffe970ba967 UE4Editor-Core.dll!FOutputDevice::LogfImpl() [d:\build++ue4\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:71]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe96958ad4 UE4Editor-CoreUObject.dll!FUntypedBulkData::SerializeBulkData() [d:\build++ue4\sync\engine\source\runtime\coreuobject\private\serialization\bulkdata.cpp:1260]
PackagingResults: Error: [Callstack] 0x00007ffe96ff0df7 UE4Editor-Core.dll!FDebug::AssertFailed() [d:\build++ue4\sync\engine\source\runtime\core\private\misc\assertionmacros.cpp:417]
PackagingResults: Error: [Callstack] 0x00007ffe968429f3 UE4Editor-CoreUObject.dll!FMemoryWriter::Serialize() [d:\build++ue4\sync\engine\source\runtime\core\public\serialization\memorywriter.h:42]
PackagingResults: Error: [Callstack] 0x00007ffe96958ad4 UE4Editor-CoreUObject.dll!FUntypedBulkData::SerializeBulkData() [d:\build++ue4\sync\engine\source\runtime\coreuobject\private\serialization\bulkdata.cpp:1260]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe96adcf4f UE4Editor-CoreUObject.dll!UPackage::Save() [d:\build++ue4\sync\engine\source\runtime\coreuobject\private\uobject\savepackage.cpp:5586]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe79ee91f6 UE4Editor-UnrealEd.dll!UEditorEngine::Save() [d:\build++ue4\sync\engine\source\editor\unrealed\private\editorengine.cpp:4441]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe79d7ec87 UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::SaveCookedPackage() [d:\build++ue4\sync\engine\source\editor\unrealed\private\cookontheflyserver.cpp:3988]
PackagingResults: Error: [Callstack] 0x00007ffe96adcf4f UE4Editor-CoreUObject.dll!UPackage::Save() [d:\build++ue4\sync\engine\source\runtime\coreuobject\private\uobject\savepackage.cpp:5586]
PackagingResults: Error: [Callstack] 0x00007ffe79ee91f6 UE4Editor-UnrealEd.dll!UEditorEngine::Save() [d:\build++ue4\sync\engine\source\editor\unrealed\private\editorengine.cpp:4441]
PackagingResults: Error: [Callstack] 0x00007ffe79d7ec87 UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::SaveCookedPackage() [d:\build++ue4\sync\engine\source\editor\unrealed\private\cookontheflyserver.cpp:3988]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe79d814b1 UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::SaveCookedPackages() [d:\build++ue4\sync\engine\source\editor\unrealed\private\cookontheflyserver.cpp:2896]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe79d8cbd0 UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::TickCookOnTheSide() [d:\build++ue4\sync\engine\source\editor\unrealed\private\cookontheflyserver.cpp:2372]
PackagingResults: Error: [Callstack] 0x00007ffe79d814b1 UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::SaveCookedPackages() [d:\build++ue4\sync\engine\source\editor\unrealed\private\cookontheflyserver.cpp:2896]
PackagingResults: Error: [Callstack] 0x00007ffe79d8cbd0 UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::TickCookOnTheSide() [d:\build++ue4\sync\engine\source\editor\unrealed\private\cookontheflyserver.cpp:2372]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe79bea79b UE4Editor-UnrealEd.dll!UCookCommandlet::CookByTheBook() [d:\build++ue4\sync\engine\source\editor\unrealed\private\commandlets\cookcommandlet.cpp:882]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffe79c1d0bf UE4Editor-UnrealEd.dll!UCookCommandlet::Main() [d:\build++ue4\sync\engine\source\editor\unrealed\private\commandlets\cookcommandlet.cpp:586]
PackagingResults: Error: [Callstack] 0x00007ffe79bea79b UE4Editor-UnrealEd.dll!UCookCommandlet::CookByTheBook() [d:\build++ue4\sync\engine\source\editor\unrealed\private\commandlets\cookcommandlet.cpp:882]
PackagingResults: Error: [Callstack] 0x00007ffe79c1d0bf UE4Editor-UnrealEd.dll!UCookCommandlet::Main() [d:\build++ue4\sync\engine\source\editor\unrealed\private\commandlets\cookcommandlet.cpp:586]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ff7a57fed22 UE4Editor-Cmd.exe!FEngineLoop::PreInit() [d:\build++ue4\sync\engine\source\runtime\launch\private\launchengineloop.cpp:2478]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ff7a57f5783 UE4Editor-Cmd.exe!GuardedMain() [d:\build++ue4\sync\engine\source\runtime\launch\private\launch.cpp:135]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ff7a57f59ea UE4Editor-Cmd.exe!GuardedMainWrapper() [d:\build++ue4\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:145]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ff7a58048da UE4Editor-Cmd.exe!WinMain() [d:\build++ue4\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:276]
PackagingResults: Error: [Callstack] 0x00007ff7a57fed22 UE4Editor-Cmd.exe!FEngineLoop::PreInit() [d:\build++ue4\sync\engine\source\runtime\launch\private\launchengineloop.cpp:2478]
PackagingResults: Error: [Callstack] 0x00007ff7a57f5783 UE4Editor-Cmd.exe!GuardedMain() [d:\build++ue4\sync\engine\source\runtime\launch\private\launch.cpp:135]
PackagingResults: Error: [Callstack] 0x00007ff7a57f59ea UE4Editor-Cmd.exe!GuardedMainWrapper() [d:\build++ue4\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:145]
PackagingResults: Error: [Callstack] 0x00007ff7a58048da UE4Editor-Cmd.exe!WinMain() [d:\build++ue4\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:276]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ff7a580584e UE4Editor-Cmd.exe!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:283]
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffedfd33dc4 KERNEL32.DLL!UnknownFunction []
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: [Callstack] 0x00007ffedfe83691 ntdll.dll!UnknownFunction []
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error:
UATHelper: Packaging (Windows (64-bit)): LogWindows: Error: end: stack for UAT
PackagingResults: Error: [Callstack] 0x00007ff7a580584e UE4Editor-Cmd.exe!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:283]
PackagingResults: Error: [Callstack] 0x00007ffedfd33dc4 KERNEL32.DLL!UnknownFunction []
PackagingResults: Error: [Callstack] 0x00007ffedfe83691 ntdll.dll!UnknownFunction []
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMultiByProfile.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMultiForObjects.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceSingle.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceSingleByProfile.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceSingleForObjects.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:CapsuleTraceMulti.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:CapsuleTraceMultiByProfile.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:CapsuleTraceMultiForObjects.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:CapsuleTraceSingle.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:CapsuleTraceSingleByProfile.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:CapsuleTraceSingleForObjects.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:DrawDebugCylinder.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:LineTraceMulti.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:LineTraceMultiByProfile.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:LineTraceMultiForObjects.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:LineTraceSingle.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:LineTraceSingleByProfile.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:LineTraceSingleForObjects.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:SphereTraceMulti.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:SphereTraceMultiByProfile.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:SphereTraceMultiForObjects.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:SphereTraceSingle.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:SphereTraceSingleByProfile.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.KismetSystemLibrary:SphereTraceSingleForObjects.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or BoolProperty /Script/Landscape.LandscapeSplineConnection:End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/Engine.BatchedLine:End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/AIModule.NavLocalGridManager:FindLocalNavigationGridPath.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/FunctionalTesting.FunctionalTestUtilityLibrary:TraceChannelTestUtil.End
LogUObjectHash: Warning: Ambiguous search, could be StructProperty /Script/Engine.KismetSystemLibrary:BoxTraceMulti.End or StructProperty /Script/MeshEditor.OverlayLine:End
PackagingResults: Error: end: stack for UAT
UATHelper: Packaging (Windows (64-bit)): Took 180.1767409s to run UE4Editor-Cmd.exe, ExitCode=3
UATHelper: Packaging (Windows (64-bit)): ERROR: Cook failed.
UATHelper: Packaging (Windows (64-bit)): (see C:\Users\daryl.tebug\AppData\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_4.21\Log.txt for full exception trace)
PackagingResults: Error: Cook failed.
UATHelper: Packaging (Windows (64-bit)): AutomationTool exiting with ExitCode=25 (Error_UnknownCookFailure)
UATHelper: Packaging (Windows (64-bit)): BUILD FAILED
PackagingResults: Error: Unknown Cook Failure
LogSlate: FSceneViewport::OnFocusLost() reason 0
LogSlate: Took 0.000776 seconds to synchronously load lazily loaded font ‘…/…/…/Engine/Content/Slate/Fonts/DroidSansMono.ttf’ (77K)