What to do right now
- Download or copy the archive again and compare its size with the original.
- If that is not possible, keep the damaged file and work on a copy.
- Rebuild a new archive from the entries that are still intact.
Step by step
Get a fresh copy if you can
Most ZIP errors come from interrupted downloads or failed copies to USB sticks. A new download or copy from the original source is the cleanest fix.
Note which entries fail
Your extraction tool usually names the files with CRC errors. These are the ones that are damaged; the others may extract correctly.
Inspect the archive
In Damaged file repair, choose the ZIP. FileFix Ultimate reads the local entries, the central directory at the end and each entry's checksum, and reports what is missing or wrong.
Create a repaired archive
Create the repaired copy. It is a new ZIP built from the entries that could be read, with a correct central directory, so standard tools can open it.
Check the extracted files
Extract the repaired archive and open the important files. Entries that failed their checksum are reported; their content may be incomplete.
What the errors mean
Each entry in a ZIP stores a CRC-32 checksum of its original data. When extracted data does not match, the tool reports a CRC error: something changed those bytes after the archive was created, often a bad copy, a failing drive or a fake-capacity USB stick.
The central directory, the index of all entries, sits at the very end of the file. If the archive is truncated, the index is missing and tools report an unexpected end of archive. The entries before the cut are often complete, and each one also has its own local header, which is what a rebuild uses.
Multi-part and other archive formats
Split archives need all their parts; a missing part cannot be replaced. RAR and 7z archives are found during deletion recovery but are not repaired by FileFix Ultimate.
When it won't work
- Entries whose data was damaged keep their errors; a CRC failure means the original bytes are not available.
- Encrypted ZIP entries cannot be checked or repaired without the password.
- Data after the point where a truncated archive ends is not in the file.
How FileFix Ultimate helps
- Recovers entries from local headers when the central directory is missing or damaged.
- Checks every entry's CRC and decompresses it to confirm it is intact.
- Writes a new archive and keeps the original unchanged.
- Uses the same container checks for DOCX, XLSX, PPTX and HWPX files.
FileFix Ultimate is free, works offline and never writes to the drive you are recovering from. Check the signature before you run it.
Frequently asked questions
Can a CRC error be fixed?
The archive can be rebuilt so it opens, but the damaged entry's data cannot be corrected without the original. The other entries are unaffected.
Why do I keep getting CRC errors on files from the same USB stick?
That points to the stick, not the archives. It may be failing or have fake capacity. Copy what you can and run a fake capacity check.
Does it repair RAR or 7z archives?
No. Only ZIP-based files are repaired. RAR and 7z are recognised when recovering deleted files.
Can the same method help with a damaged DOCX or XLSX?
Yes. Office files are ZIP containers, so a rebuild from local entries often makes them openable again. See the guide on repairing Word, Excel and PowerPoint files.