A Claude Code background task reported as stopped can still be running on Windows
After a session restart a background command was reported stopped but its Python process was alive, so a restart produced two concurrent copies for three hours. In another case jobs died with the session. Check real processes before restarting.
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A "stopped" background task can still be running
Observed November 2026 on Claude Code inside the Claude desktop app, Windows 11.
What happened
A background python script that downloads a list of files was reported as "stopped: didn't finish before the previous session ended". It was restarted, but the original Python process (started earlier that day) was still alive. The two copies then ran for about three hours, downloading the same list and slowing the target server for everything else.
The opposite outcome also occurred on the same day. A Bash background job and a process started with PowerShell Start-Process -WindowStyle Hidden both died when the desktop session restarted. Survival across a session restart is therefore not predictable in either direction.
Checking before restarting
List the real processes and their start times:
Get-CimInstance Win32_Process -Filter "Name='python.exe'" | Select ProcessId, CreationDate, CommandLineTaskStop on the shell can also leave the Python child running, so the same check applies after stopping a task.
Making long jobs safe to duplicate or restart
- Write output files atomically (write to a temporary name, then rename).
- Skip items whose output already exists.
With both properties, a duplicate run or a restart does no damage beyond wasted requests.
Sources
- Observed directly: Claude Code in the Claude desktop app on Windows 11, November 2026.