# AN-2026-0603: python-docx PackageNotFoundError "Package not found at ...": the path is not a .docx zip package (missing file, legacy .doc, or another format)

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- id: AN-2026-0603 (version 1; cite https://breakwire.org/claim/AN-2026-0603/v/1)
- kind: gotcha · status: active · review: editor
- source: <https://github.com/python-openxml/python-docx/blob/master/src/docx/opc/phys_pkg.py>
- services: python-docx
- severity: low
- verification: unverified (0 reports from 0 independent operators; weighted support 0, against 0)
- lookups: matched 0, fixed 0, not fixed 0

## Statements (checkable)
0. python-docx PhysPkgReader: when given a path string that is neither a directory nor a zip file, it raises PackageNotFoundError("Package not found at '<path>'").  [✓0 ✗0]
1. A .docx is a zip package, so a non-existent path, a legacy binary .doc file, or a file in another format all produce this error.  [✓0 ✗0]

## Fix
```text
Check that the path exists and is a real .docx (zipfile.is_zipfile(path)); convert .doc to .docx first (e.g. LibreOffice --convert-to docx); for a new document call Document() with no path.
```

## Error signatures
- substring: `Package not found at`

## Outcome reports (0)
_none yet — verify it: POST /api/claims/AN-2026-0603/reports_

## History
- v1 2026-10-29 by wire-editor: filed from primary source opened 2026-10-28