FilenameToLongPackageName failed to convert ''

When I building my project and trying to launch it this error appears:

Error: Fatal error: [File:D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\Misc\PackageName.cpp] [Line: 771]
Error: FilenameToLongPackageName failed to convert ‘’. The Result would be indistinguishable from using ‘’ as the InFilename.

I’ve already tried to delete Intermediate and Binaries folders and rebuild project, but it doesn’t helped.
Full callstack:
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: begin: stack for UAT
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: === Critical error: ===
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error:
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: Fatal error: [File:D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\Misc\PackageName.cpp] [Line: 771]
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: FilenameToLongPackageName failed to convert ‘’. The Result would be indistinguishable from using ‘’ as the InFilename.
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error:
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error:
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error:
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error:
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e0a4ab3b HexArena.exe!FPackageName::FilenameToLongPackageName() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e0a6bdf4 HexArena.exe!FPackagePath::TryFromMountedName() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e0b282b3 HexArena.exe!UE::Serialization::GetLinkerLoadFromOwner() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e0b2e9d3 HexArena.exe!LoadPackageAsync() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e4b2dda5 HexArena.exe!UGameplayTagsManager::LoadGameplayTagTables() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e4b2cc46 HexArena.exe!UGameplayTagsManager::InitializeManager() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e5e6e8ef HexArena.exe!UEngine::InitializeObjectReferences() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e5e6857a HexArena.exe!UEngine::Init() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e5423565 HexArena.exe!UGameEngine::Init() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6dee99c98 HexArena.exe!FEngineLoop::Init() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6deeb682e HexArena.exe!GuardedMain() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6deeb6a0a HexArena.exe!GuardedMainWrapper() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6deeb9a8c HexArena.exe!LaunchWindowsStartup() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6deecb244 HexArena.exe!WinMain() []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff6e703d76a HexArena.exe!__scrt_common_main_seh() [d:\a01_work\20\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff8ef4b7034 KERNEL32.DLL!UnknownFunction []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: [Callstack] 0x00007ff8f14a2651 ntdll.dll!UnknownFunction []
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error:
LogPlayLevel: Error: [2022.06.09-16.56.24:947][ 0]LogWindows: Error: end: stack for UAT

Hey Fedotich,

There are a couple of things you can try to resolve this. First, if you go to Editor Settings > General - Experimental, you can click a check box to Enable Long File Paths. This may help with your situation. If it does not, can you move the project itself to a root folder on one of your disks? That will reduce the file path length and may resolve the issue as well.

Please let me know if either of these solutions work for you!

1 Like

Hey, I tried both of these methods but none of them worked for me

Well, I found out that the problem was in gameplay tags. somehow I left this charactes in this field and they was crusing game

4 Likes

thank you!!! - I spun my wheels for half a day, re-installing things, till I saw your post… I had an “empty” entry there!

1 Like

I don’t get it, If I remove those I still get the error. What did you add or remove?

Hey, this tab is for gameplay tags system. Accedently leaving incorrect string can cause this error, but this error can also be caused by other purposses.

1 Like

I don’t understand did you delete these or add them?

I just deleted them

I fixed this by just copying and pasting the intended directory into the “List of maps to include in a packaged build” field, because when you try to input it the normal way, it adds the …\ which unreal can’t read.
Worked for me after that.

1 Like