Multi-Purpose Internet Mail Extension or Mime files can be opened and decoded by file decompression utilities such as Corel WinZip 18.5, Microsoft Outlook 2013, Apple Mail, Mozilla Thunderbird or KMail. These utilities are used by the Windows, Mac OS and Linux operating systems.
The Mime file is an encoded file that is used by email programs and contains 8-bit encoded data. It also includes characters other than the US ASCII character set that is used to support file attachments and uses a richer character set, rather than sending standard 7-bit through email. If Mime files, which typically have the extension .mim, are not recognized by email programs, they can be decoded using a file compression utility.