# ERROR: Cannot find a version of package that satisfies the requirement package==1.2.3 (from versions: none)
ERROR: No matching distribution found for package==1.2.3

- **ID:** `python/pip-conflicting-extra-index-url`
- **Domain:** python
- **Category:** network_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

An --extra-index-url points to a private index that does not host the requested package/version, and pip does not fall back to PyPI for that name.

## Version Compatibility

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

## Workarounds

1. **** (88% success)
   ```
   Use both indexes explicitly: pip install --index-url https://pypi.org/simple --extra-index-url https://private.example.com/simple package
   ```
2. **** (85% success)
   ```
   Verify the private index hosts the version: curl -s https://private.example.com/simple/package/ | grep 1.2.3
   ```
3. **** (90% success)
   ```
   Publish the missing version to the private index or pin to a version it hosts
   ```

## Dead Ends

- **** — Trusted-host only affects TLS verification; the package is simply absent from the index. (90% fail)
- **** — Replacing the index removes PyPI access entirely, so public deps also fail. (80% fail)
- **** — The package is not present in the index; retries do not change availability. (95% fail)