Move File doesn't work?

Development Programming & Scripting C++
,
1 
bool RenameFile(const FString& OldFilename, const FString& NewFilename)
{
	// Get the file manager instance
	IPlatformFile& FileManager = FPlatformFileManager::Get().GetPlatformFile();

	// Attempt to rename the file
	if( FileManager.MoveFile(*OldFilename, *NewFilename) )
	{
		UE_LOG(LogTemp, Warning, TEXT("Old Name : %s"), *OldFilename);
		UE_LOG(LogTemp, Warning, TEXT("New Name : %s"), *NewFilename);
		return true;
	}
	else
	{
		UE_LOG(LogTemp, Warning, TEXT("Old Name : %s"), *OldFilename);
		UE_LOG(LogTemp, Warning, TEXT("New Name : %s"), *NewFilename);
		UE_LOG(LogTemp, Error, TEXT("FileManager.MoveFile FAILED!"));
		return false;
	}
}

The output I get from this is :
LogTemp: Warning: Old Name : …/…/…/…/…/…/ZZZ/Projects/Game/Content/GameData/Buildings/all0.txt
LogTemp: Warning: New Name : …/…/…/…/…/…/ZZZ/Projects/Game/Content/GameData/Buildings/all0.backup.1.txt
LogTemp: Error: FileManager.MoveFile FAILED!

This file does exist and is accessible because it was created by SaveStringToFile on a previous run of PIE (not the current one, though i found no way to ‘close’ a file the usual c++ way either). Either way I can delete the file in explorer fine, PIE running or not.

Am I doing this wrong, or is FPaths::ProjectContentDir() which rreturned that wacking looking path the problem here?

2

IFileManager::Get().Move also does not work for me. the file just disappear.