If 7-Zip cannot open an archive or compressed file and you see Cannot open file as archive error message, here's what you can do.

You no longer need third-party apps if you want to open zip files on iOS. Rar files? That's another story.

While most formats will archive and compress a group of files for you, a few formats are only designed to do one or the other. Tar, for example, only archives files, while gzip and bzip only ...