---
id: data-transfers.why-cant-this-transfer-resume-part-way
url: https://storagestudio.us/faq/data-transfers/why-cant-this-transfer-resume-part-way
category: "Data Transfers"
subcategory: "Downloads and large files"
question: "Why does the log say a transfer can't be resumed part-way?"
alt_questions:
  - "This service can't send part of a file"
  - "transfer runs in one pass message"
  - "Resuming part-way only works when the file is coming down to this Mac"
  - "This transfer isn't a single file, so it runs in one pass"
  - "why isn't my upload resumable"
short_answer: "Part-way resume only works for one large file downloading to your Mac from a source that can send partial files. Uploads, cloud-to-cloud transfers, folders and servers that only send whole files run in one pass instead."
tags: ["resume", "log messages", "uploads"]
related: ["https://storagestudio.us/faq/data-transfers/large-downloads-resume-where-they-left-off", "https://storagestudio.us/faq/data-transfers/where-is-the-transfer-log"]
applies_to: "app>=4.16"
last_reviewed: 2026-10-01
---

# Why does the log say a transfer can't be resumed part-way?

Resuming part-way only applies to **one large file coming down to your Mac** from a source that can send part of a file. When a transfer doesn't fit, the log explains which case you hit:

- *"This service can't send part of a file…"* — the server only sends whole files, so the download runs in one pass.
- *"Resuming part-way only works when the file is coming down to this Mac."* — uploads and cloud-to-cloud transfers run in one pass.
- *"This transfer isn't a single file…"* — folders don't need it; a rerun just sends what's missing.

None of these is an error; the transfer still runs. It just means an interruption restarts that one file rather than continuing it.

Related: [Large downloads that resume](https://storagestudio.us/faq/data-transfers/large-downloads-resume-where-they-left-off)