How do I find out which RAR file is corrupt?

Question

I have a RAR I downloaded made up of multiple files. When trying to extract it, it tells me the data is incomplete, something bad with one of the files. Considering I had to download multiple large files, is there a way to find out exactly which of the files I should re-download?

I'm on a Mac.

Solution 1

Consider downloading UnRarX to test the files for integrity.

Open UnRarX.app, click Browse (or Cmd+B), select your RAR files. I guess selecting the first one should be enough. Then, click Test. It will scan each of the RAR files and give you a more specific error message about which one is corrupt.

I prefer UnRarX over the default Archive Helper in OS X, as it sometimes gives better results when opening password-protected RAR files.

Solution 2

For me, the accepted answer didn't work for some reason. Maybe UnrarX has changed something in their later versions, or there was something funny about my files. It just didn't show the correct result for my files. Anyways, here's how I solved it:

I downloaded the rar command line tools from Rarlab. Download the 'RAR for OS X' package. Even though it says trial, the unrar part is actually freeware. To test the archives run

unrar t /path/to/file.part01.rar

It will show you exactly which files are corrupted. After replacing the files, you can extract using a gui program or by running

unrar x /path/to/file.part01.rar

Solution 3

What program are you using to extract the rar files? It should be telling you which file is corrupt.

You say that you downloaded several files, looking at them in Finder you might be able to tell the corrupt one by the fact that the file size is noticeably smaller than the rest. Ideally you don't need to redownload the entire bad file. The original poster of the RAR should have also included .Par or .Par2 files just for this situation.

A program like MacPar Deluxe will not only unrar your files but utilize the .par files to rebuild any bad or sometimes missing data.

Comments

[Rodrigo Jimenez]

I use "The Unarchiver", it doesn't say much. None of the files seem to have drastically different sizes. I'm trying MacPar now. Note that the first RAR file has an "exe" extension - not sure if it matters.

[Rodrigo Jimenez]

A checksum error (2) occurred during Unrar, or an invalid password was entered