Not enough disk space

Rendering a clip writes a video file to your drive, and 4K or ProRes files can be large. Before a render starts, Butter Motion estimates how much space it needs and compares it with what's free. If the estimate doesn't fit, it asks instead of failing halfway: This render may not fit: it needs about X GB, the drive has Y GB free. Render anyway?

It's a question, not a refusal. Render anyway goes ahead, because the estimate is approximate and the call is yours. Closing the question leaves the generation untouched, ready to render whenever you like.

The panel also shows a warning strip above your generations when the drive drops below 5 GB free: Low disk space · N GB left · renders may fail. So you hear about it before any render is at stake.

A render that doesn't happen costs you nothing. Rendering never spends credits, so the generation is untouched either way.

How to fix it

  1. Free up space on the drive you're rendering to. Empty the Trash (or Recycle Bin), remove files you don't need, and clear out old exports. Even a few gigabytes is usually enough for a single clip.
  2. Render somewhere with more room. You can change where Butter Motion saves renders in the account popover in the panel (click the credits chip in the header), under Render output.

Render output folder switch in the account popover Point it at a drive or folder with free space:
- Project folder saves the render next to your Premiere project.
- Custom folder lets you pick any folder you like, for example one on a larger external drive.
3. Retry the render. Once there's space, run it again. Nothing about the generation changed, so it renders exactly as before.

The account popover in the panel, the Render output section with Project folder and Custom folder
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High resolutions and transparent (ProRes 4444) output produce bigger files: a transparent 4K clip weighs roughly 0.5 to 0.8 GB for every 5 seconds, so a handful of alpha renders can quietly eat several gigabytes. If you're tight on space, delete old renders you no longer use, or pick a shorter clip / lower resolution. See Duration, format & resolution.

If it keeps happening

If you have plenty of free space and the panel still asks about it before every render, email support@buttermotion.com with your account email, your operating system, and the render folder you're using. See Contact support.