---
title: 'FTP Error: “Could Not Write to Transfer Socket: EPIPE”'
description: 'What causes the FTP error "Could not write to transfer socket: EPIPE" during uploads and how to resolve it.'
url: https://www.medialab.co/support/troubleshooting/upload-processing/ftp-could-not-write-to-transfer-socket
---

# FTP Error: “Could Not Write to Transfer Socket: EPIPE”

This error occurs when the **control connection** of your FTP session is closed during a file transfer.

Each FTP connection uses two TCP connections:

1. **Control connection** – Handles commands and remains open during transfers.
2. **Data connection** – Handles the actual file transfer.

During an active transfer, the control connection stays idle. If a firewall or router is misconfigured to close idle connections, the transfer will fail with this error.

### How to Resolve

- **Try a different FTP upload program** – Some clients keep idle control connections alive more reliably.
- **Contact your IT department** – They may need to adjust firewall or router settings to keep the control connection open during large file transfers.