Troubleshooting
Find the fix from what you see: Nucleus Co-op does not open, a game does not launch or connect, a controller drives two windows, windows look stretched, or the game runs slowly.
Start from what you see. Most problems have a fix that takes a minute, and the handler notes often mention the ones that are specific to a game.
Before anything else
- Use the latest Nucleus Co-op and the latest handler. The library shows Update to vN when a handler has a newer version.
- Read the handler notes (Game options › Handler Author's Notes). They list the game version, the options, and how to connect the copies.
- Run the game once without Nucleus, change a graphics setting, apply, and quit.
- Check where Nucleus Co-op lives: its own folder at the root of an NTFS drive, not in
Program Files, OneDrive or your user folder (Install).
Find your symptom
| What you see | Where to look |
|---|---|
| Nucleus Co-op doesn't open, closes at once, or shows a blank window | The app does not start |
A file is missing, often ProtoInputHooks64.dll | The app does not start |
| Only one copy of the game starts, or the copies crash | A handler does not work |
| The copies start but can't see each other | A handler does not work |
| "File not found" or config errors at launch | A handler does not work |
| A OneDrive warning, or your Documents folder moved | A handler does not work |
| A controller doesn't show up in the lobby | Controller problems |
| One controller moves two players, or the camera spins | Controller problems |
| The mouse cursor is stuck, or you can't close the game | Keyboards and mice |
| Windows look stretched or blurry | Performance |
| Low or uneven frame rate | Performance |
Still stuck?
Ask on Discord: it's the fastest way to get help, and handler authors are there. To report a bug, follow Report a bug so people can reproduce it.