Windows Server · Python hosting
WinError 32: runtime.log is being used by another process
Redeploy fails because Waitress still holds runtime.log open. Stop the app task, then deploy again (fixed in 0.6.9+).
What you’re seeing
Redeploy or folder sync fails with WinError 32 — the process cannot delete or replace runtime.log (or the build directory) because another process still has the file open.
Why it happens
The app runtime (Waitress / Streamlit / etc.) is still running and holding the log handle while the deployer tries to wipe the build folder.
The fix
- Stop the app task (e.g.
iVistaarApp-<slug>) then redeploy - Or upgrade to a host that stops the app before sync (iVistaar 0.6.9+)
Avoid this class of problem
iVistaar stops the per-app task before syncing the connected folder on redeploy, which is how you avoid WinError 32 during auto-deploy on Windows.
Publish without the IIS tax
iVistaar is an internal deployment control plane for Windows Server/IIS that gives Flask, Dash, and Streamlit apps an org URL without Git or cloud services. Free demo includes 3 sites.