Method 1: Repair Corrupted or Damaged RAR/ZIP File Using WinRAR
1. Right-click on your corrupted RAR or ZIP file and select “Open with WinRAR” from the context menu.
2. When WinRAR opens, click the Tools menu and select Repair archive.
3. Click the Browse button to select the destination location where the repaired RAR/ZIP file has to be saved. Leave the archive type as what it was and click OK.
4. After WinRAR has completed repairing the archive, click the Close button.
5. You’ll see a repaired archive created in the same folder as the corrupted archive.Method 2: Extract Broken RAR/ZIP Archive
1. Unfortunately, after repairing RAR/ZIP archive, WinRAR may still say the file is corrupt. Then you can attempt to extract the content in the RAR/ZIP archive. WinRAR has an option to extract broken files using which you can actually extract the broken or corrupt files – ignoring all the errors no matter what.
2. Double-click your corrupted RAR or ZIP archive to open it in WinRAR. Click Extract to in the toolbar at the top.
3. Choose the destination folder where you want to extract the files. But most importantly, you have to check the Keep broken files option under the Miscellaneous section.
4. Click OK and wait while the files are extracted. Eventually you’ll have all the files present in your RAR/ZIP archive.
Generally speaking , it's much better to re-download the file. While it may be possible to repair a RAR file to the point where some information can be extracted, you are very unlikely to be able to restore the whole file, since the RAR format compresses the contents by removing redundant information - that very same information that could be used to reconstruct corrupt or missing data in uncompressed files!