# Troubleshoot Diagnose and fix common FiftyOne issues: dataset persistence, App connectivity, MongoDB errors, video codecs, and more. ## Install ```bash curl -sL skil.sh | sh -s -- voxel51/fiftyone-skills ``` When prompted, select **fiftyone-troubleshoot** from the menu. ## Requirements - [FiftyOne](https://docs.voxel51.com/getting_started/install.html) ## Usage Ask your AI assistant: ```default "My dataset disappeared after restarting, how do I get it back?" "The FiftyOne App won't open, it just hangs" "I'm getting a MongoDB connection error" "Video samples show a codec error in the App" "My operator is registered but not showing up in the App" ``` The skill identifies the root cause, explains what went wrong and why, proposes a fix, and waits for your confirmation before applying anything. ## Covered issues - Dataset persistence and MongoDB connectivity - App launch failures and port conflicts - Plugin and operator not appearing - Video codec incompatibilities - Notebook connectivity (`fo.launch_app` in Jupyter) - Performance issues with large datasets ## See also - [FiftyOne FAQ](https://docs.voxel51.com/faq/index.html) - [Discord community](https://discord.gg/fiftyone-community)