I'd like to use Archive Utility (the built-in OSX archive tool) to decompress some .cbz and .cbr files. Unfortunately, Archive Utility doesn't seem to recognize .cbz or .cbr as a zipped file, so if I try to "Open With" Archive Utility, it re-zips the file; if I try to "Expand Archive" from Archive Utility itself, it doesn't recognize the extension and won't allow me to select the greyed-out file.
When I rename a .cbz to .zip file, Archive Utility works fine.
With .cbr files, however, after I rename the extension to .zip, Archive Utility will rezip as a .zip.zip file (or .zip.cbgz file, depending on my settings in Archive Utility). If I open that .zip.zip file in Archive Utility, it will extract it back to a regular .zip file, but it remains an unopenable archive.
Any ideas on how I can force an unzip?
Due to administrator settings (I'm on a work computer), I must use Archive Utility and can't easily have any other unzip or archive software installed.
Edit: I've also tried it from the terminal using the "open" command with the same (.zip.zip) results.