Troubleshooting video uploads in Buffer

If you're having trouble uploading or publishing a video in Buffer, this guide will help you troubleshoot common issues like failed uploads, slow processing, or video posts not appearing as expected.

The most common issues come from using videos outside of the suggested requirements, so be sure to check the limits below before proceeding to other troubleshooting steps!

In this article:

First: check video requirements
Slow or stuck uploads
Thumbnails or post appearance issues

First: check video requirements

Make sure your video meets these key guidelines:

Format: MP4, MOV, AVI, or M4V
Codec: H.264
Max size:
- 40MB (Mastodon)
- 100 MB (Instagram)
- 1 GB (Facebook, X/Twitter, LinkedIn, Pinterest, TikTok, Threads)
- 10GB (YouTube Shorts)
Max resolution: 1280×720
Avoid raw or high-end camera formats (e.g., ProRes, RED)

💡Tip: If your video is too large, too long, or uses an unsupported format, it may fail to upload or process correctly.

Slow or stuck uploads

Buffer processes and transcodes videos when uploading, which can take longer for large files or slower connections.

Try uploading a smaller or lower-resolution version
Check your internet connection
Use standard MP4 (H.264) format for faster, more reliable uploads

If your video starts to upload but fails to save or publish (or you get the error “Buffer’s servers couldn’t be reached”), it may be caused by:

Ad blockers or browser extensions
Strict privacy settings in your browser
VPNs or network firewalls

👉 Try posting from an incognito/private window, disabling ad blockers and VPNs, and switching networks. Learn more about common upload issues here.

Thumbnails or post appearance issues

Sometimes your video publishes, but the visual result or metadata (thumbnail, title) isn’t what you expected. Here’s what to check:

Some networks (Instagram, TikTok, Pinterest) let you choose a thumbnail from your video via Buffer.
Other networks (Facebook, LinkedIn, Mastodon, Bluesky) may ignore custom thumbnails due to API or platform limitations.
Titles may appear differently (or not at all) depending on the network:
- Facebook - the title will appear at the top of the video post
- X/Twitter - A title will be used if the video is outside of X/Twitter's file limits and has to be displayed as a link to Buffer's video player
- Pinterest - The title of the video will be shown at the bottom of the video in the feed.

Troubleshooting:

After uploading, check if the “Edit Thumbnail” option appears in Buffer (for the networks that support it).
If your custom thumbnail or title does not show after publishing, review the specific network’s limitations (see the “Sharing videos through Buffer” article).
Also check that your video meets the network’s aspect ratio/length/file requirements — incorrect specs may cause fallback behavior (e.g., link preview instead of native video).

💡Tip: If your post looks different than expected, check the social network’s limitations. A link preview often means the video didn’t meet the platform’s requirements.

Quick checklist

✅ Use MP4 (H.264)

✅ Stay within size and length limits for each social network

✅ Avoid VPNs/ad blockers while uploading

✅ Check for browser conflicts (try incognito mode)

✅ Try a test upload with a small video

✅ Review how each network handles videos

Still need help?

Contact Buffer support at hello@buffer.com with:

Your video’s format, size, and length
What happened vs what you expected
Any error messages or screenshots

We’ll help troubleshoot from there!