I have more than 20 gigabytes of RAR files, of which some have been damaged.
Can anyone tell me how to find out which RAR files are corrupt without trying to extract each archive?
Using 7-Zip, you can select multiple RAR or other archives and select Test in the 7-Zip File Manager to test the integrity of all of them.
Alternatively, you can enable 7-Zip's shell integration feature1, use Windows Search to find all of the RAR archives (in Windows 7, use the search string
type:rar), then select all of the results of the search, right-click on the results, and under 7-Zip, select Test archive.
1To enable shell integration, open the 7-Zip File Manager, select Options from the Tools menu, select the 7-Zip tab, and check the Integrate 7-Zip to shell context menu check box. Note that this requires administrator privileges; in Windows Vista and Windows 7, right click on the icon for the 7-Zip File Manager, click on Run as administrator, and click through the UAC prompt.
This is a bit slow but works well for me. I open a dos window using command.com then change directory to winrar directory. Then type winrar t -r e:*.* this is to test all files on e drive including sub directories. if you only want to check rar files then e:*.rar will check all rar files on e drive. I found this VERY useful because winrar nor 7zip seem to recognize cbr or cbz files as archives if you use the integrity tester in the regular program interface. Also being able to test all sub-directories at one go is helpful. All errors will be output to a temp file that you will need to copy and save. Backslash after the e: doesnt seem to be saved in the message.