0x80070020 — The process cannot access the file because it is being used Another process has an exclusive lock on the file.
What we do first
- Pause the backup agent while you work
- Restart the indexer or the preview host
- Close the other instance of the application
If it comes back
Do not keep design folders inside a folder that a backup agent scans during the day.
Checked 2026-10-05 — R. Okonkwo.
Before changing anything
The code above is what an application reports; it is not a diagnosis of what went wrong. Two checks are worth doing before permissions are touched: whether the file is on a volume the application can actually reach, and whether the file was moved or renamed since it was last opened. Both report as this code more often than a permission problem does.
Pages in this section describe the code as applications report it. Where a fix is listed here, it is one the library has seen work on a real file; where nothing has been confirmed, the page says so instead of guessing at a cause.