# Troubleshooting & FAQ (https://docs.fuser.studio/docs/apps/troubleshooting)

Most app issues are recoverable — your last working version and full history are
always safe. Here's how to read the common ones.

## Build & save errors [#build--save-errors]

* **The chosen model is unavailable** — it's temporarily down or rate-limited.
  Try again, or switch to another [model](https://docs.fuser.studio/docs/apps/models.md) and continue.
* **Compile / bundle / save failed** — a code change didn't build. The editor
  flags the error with its line number and offers **Retry**. You can also
  **Revert file** to discard the change, or ask the agent to fix it.
* **A runtime error in the running app** — a **Fix runtime error** banner appears
  in the composer. Click it to load a repair prompt and send it to the agent.
* **A fork or fuse didn't complete** — the action reports the failure in its
  dialog. Your source app is unaffected; run the action again.

## "Private preview" [#private-preview]

A **Private preview** page that asks you to open the app from its workspace means
the app is an unpublished **draft** — only the project's editors can open it.
[Publish](https://docs.fuser.studio/docs/apps/publishing.md) it to make it openable by anyone with the link.

## FAQ [#faq]

    Yes. The

    **Free**

     model is the default and spends no credits. Switch to a higher-quality model only when a build needs it — see

    [Generation models](https://docs.fuser.studio/docs/apps/models.md)

    .

    A draft stays private to the project's editors. Once you

    **publish**

    , anyone with the public link can open it — hit

    **Publish**

     and share the link. See

    [Sharing & your audience](https://docs.fuser.studio/docs/apps/sharing.md)

    .

    It depends on your plan: Free publishes 1 at a time, Indie 5, and Professional and Teams have no limit. You can build as many as you like either way — the cap is only on apps published at once. See

    [Publishing & versions](https://docs.fuser.studio/docs/apps/publishing.md)

    .

    Yes. Every build is a version. Use the version switcher in focus mode to roll back to an earlier one — it's non-destructive. See

    [Publishing & versions](https://docs.fuser.studio/docs/apps/publishing.md)

    .

    Published apps carry a small

    **Made with Fuser**

     badge for your audience. See

    [Sharing & your audience](https://docs.fuser.studio/docs/apps/sharing.md)

    .

    No.

    **Unpublish**

     only removes public access — your code and version history stay intact, and you can publish again anytime.

## What's next [#whats-next]

  - [Building with the agent](https://docs.fuser.studio/docs/apps/building.md): Prompts, crafting, and one-click error fixes.

  - [Publishing & versions](https://docs.fuser.studio/docs/apps/publishing.md): States, version history, rollback, and limits.