MBX File Extension

Have a problem opening a .MBX file? We collect information about file formats and can explain what MBX files are. Additionally we recommend software suitable for opening or converting such files.

What is the .MBX file type?

MBX is a mailbox file format commonly used for aggregating multiple e-mail messages in a single text file. Historically, .mbx files were mainly found on UNIX-like operating systems, but now they are supported by other messaging tools on Mac and PC.

MBX files represent plain text files that store one email message after another. Each new message begins with the "From_" line and ends with a blank line (without any spaces). Between the From_ line and the blank line there is a message body in the RFC 2822 format.

There are several internal forms of the MBX file format: mboxo, mboxcl, mboxrd, and mboxcl2. They were created on the basis of different versions of Unix systems and employ different content rules and file locking mechanisms.

The MBX file extension is also associated with mailbox files created by Microsoft Outlook Express before version 6. They contain all messages that users have ever sent or received via Outlook Express on that particular computer including spam and junk messages.

Software to open or convert MBX files

You can open MBX files with the following programs: 

Popular Formats

Video Tutorials