What this repair actually rebuilds
ZIP files keep metadata beside each stored file and again in a central directory near the end of the archive. When that final directory is lost, many extractors reject the whole ZIP even though the file records themselves still exist. MakeFileWork walks those local records, verifies recoverable payloads with declared sizes, decompression and CRC32, keeps only records that pass, and writes a new directory plus end record. If one bounded record is damaged but a later record remains independently verifiable, the repair can return a partial archive instead of discarding everything.
When recovery is deliberately refused
This repair does not trust ZIP signatures inside compressed bytes by themselves. It can now recover standard signed data-descriptor entries only when the declared sizes, decompression result, CRC32 and following ZIP boundary all agree. It still refuses to guess through encrypted or ambiguously streamed data, ZIP64 structures and unsafe boundaries. When a damaged entry has a trustworthy declared boundary, it can skip that entry and continue; when the boundary itself is unknowable, recovery stops there.
Word, Excel and PowerPoint
DOCX, XLSX and PPTX are ZIP-based containers. The same conservative rebuild can therefore recover some Office files whose package directory is damaged while internal XML and media entries remain intact. After rebuilding an Office package, MakeFileWork now checks the required OOXML content-types file, package relationships and the Word/Excel/PowerPoint main XML part. It only reports that the recovered Office structure passed its opening checks when those core parts are present and internally consistent; otherwise it reports that the container was recovered but Office structure remains incomplete.
Privacy
The current ZIP rebuild runs locally in your browser. Your archive is not uploaded by this workflow.