Error: "SharePoint stopped accepting the app on … after files had copied"

SharePoint turned the app away part-way through a large copy and kept refusing it for 10 minutes. Usually temporary – run the task again later.

What it means

The site worked – files were copied – and then SharePoint started refusing every request from the app. The app waited and retried together for that site (5 s, 10 s, 20 s … up to 1 minute between tries; the Tasks list shows Waiting for SharePoint – it is briefly refusing the app). After 10 minutes of refusals it gives up on that site so the task can finish.

This is SharePoint protecting itself during heavy use. It is not a permission problem.

How to fix it

1. Wait 15–30 minutes.
2. Open Tasks, select the task and click Run again. With Copy if newer (incremental) only what is missing is copied.

Avoid it in large migrations

• Lower the Run … at a time number on the Tasks page (fewer tasks in parallel against the same tenant).
• Run large copies outside business hours with Schedule, and set an end time.
• Split a very large OneDrive or library into several tasks, for example by top-level folder.

Updated 2026-10-26