# OSError: [Errno 98] Address already in use

- **ID:** `python/starlette-uvicorn-address-in-use`
- **Domain:** python
- **Category:** system_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

Another process (often a previous uvicorn reloader) is already bound to the host/port.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 3.x | active | — | — |

## Workarounds

1. **** (92% success)
   ```
   Find and kill the holder:
lsof -i :8000
kill -9 <PID>
   ```
2. **** (90% success)
   ```
   Run on a different port:
uvicorn app:app --port 8001
   ```

## Dead Ends

- **** — Reload doesn't free the port; it spawns another process that fails to bind. (85% fail)
- **** — More workers compete for the same port and worsen the conflict. (90% fail)