finding a corrupted part from the parts of a split archive

Question

I have 7 files with extensions like xyz.rar.001 - xyz.rar.007 clearly they are parts of a single file. I have all the 7 parts. I join them using a file joiner into a single file xyz.rar and try to unrar them with WINRAR , it says that archive is corrupted It is clear that 1 or 2 parts are corrupted. IS THERE ANY WAY TO FIND THEM ? Please help I don't want to re download all of them NOTE- winrar can detect a corrupt part if the parts were splitted using winrar (with extensions like part1.rar , part2.rar etc. ) but not if they are named as rar.001

Answer 1

Parts .001 - .006 should have the same size. Check if there is a file with a different byte size.

Are there multiple files in the RAR or just the one? With multiple you could run a Test and see which is the first file to fail.

I think it's strange that there is a second tool used to split the RAR archive up. (e.g. HJSplit) This lets me think that .002 could be a RAR archive too. Try opening xyz.rar.001 with WinRAR and test/exctract. It happens more that RAR archives have the extension .001 instead of .rar. An example.

Naming your archives in WinRAR like this can be accomplished by putting "xyz.rar.001" as Archive name on the General tab and checking "Old style volume names" on the Advanced tab.

If I then join the files with HJSplit, I get one .rar file (that is corrupt). When I Test it, it says "Next volume is required". In the diagnostic messages I can see "The required volume is absent" and "CRC failed in X. The file is corrupt"

If there is one file stored inside the RAR and the RAR is indeed just chopped up into 7 pieces, there is no way of telling without additional files such as .sfv or .par2. (unless the RAR does not use compression: you can parse the underlying file for errors and calculate the part where it goes wrong)