---
title: 'Troubleshooting file upload failures'
description: 'Common causes of failed file uploads, such as firewalls, NAS sources and unstable connections, and alternative ways to upload.'
url: https://www.medialab.co/support/troubleshooting/upload-processing/troubleshooting-file-upload-failures
---

# Troubleshooting file upload failures

File uploads in MediaLab can fail for several reasons. Below are the most common causes and solutions.

### Common Causes

- **Firewall restrictions** – Corporate firewalls may block large uploads. Contact your IT department.
- **Network-attached storage (NAS)** – Uploading directly from NAS can cause disruptions. Copy the file to your local computer first.
- **Internet connection quality** – Unstable connections are the most common cause of upload issues. Use a wired connection instead of Wi-Fi if possible.
- **Outdated browser** – Ensure your browser is up to date. Check at whatbrowser.org.
- **Slow upload speed** – If your upload speed is too low for the file size, uploads may fail. See our guide on **calculating estimated upload times**.
- **Corrupted file** – Check that the file is not corrupted. Try re-exporting it from your video editor.

### Alternative Upload Methods

- **Smart routing (accelerated upload)** - Improve upload speed and reliability by routing your uploads through our global network of servers. Choose "Accelerated upload" from the **Upload** menu, then pick "Smart routing". This option is free of charge.
- **AWS upload acceleration** - Choose "Accelerated upload" from the **Upload** menu, then pick "AWS upload acceleration" to use Amazon's global network of servers. This option has an additional cost.
- **FTP uploads** – If problems persist, try FTP. It is better at resuming interrupted uploads. (Available for clients with the **Pull add-on** enabled.)

### Chunked Uploads

MediaLab offers multiple upload methods in addition to the accelerated upload.
You can enable **chunked uploads** in your user preferences. Files are uploaded in smaller parts and reassembled afterward, which improves reliability for large files or unstable connections.
Alternatively, you can toggle **resumable uploads** or **entire file uploads** to see which method works best for you.