UE5 Wont let me build the project in windows

Whether I try to build or cook the project I get a, “Build Successful” notification. But then it says,: "
UATHelper: Cooking (Windows): ERROR: System.ArgumentException: An item with the same key has already been added. Key: BlueprintJson
It also has this: "
UATHelper: Cooking (Windows): The system cannot find the path specified.
If anyone can help me much thanks is appreciated. This is my first time building in UE5, I had a similar issue in UE4 ~5 years ago but I dont remember how I fixed that. So thanks for the help.

Hi MrMorgan,

I found this thread that mentions duplicate .target files being the reason.

A reddit thread also mentions duplicate plugins.

So check your projects /Source folder!

Good luck

Thank you. It worked. I had to delete a duplicate plugin. For some reason Markteplace installed the plugin twice. Even though the plugin wasnt activated, it still stopped it from building. Quite weird.

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