Mail file

A "mail file" can refer to different things depending on the context. Here are a few possibilities:

1. Email file: In email clients like Microsoft Outlook or Mozilla Thunderbird, a mail file is a file that stores email messages, contacts, and other data. These files typically have extensions like .pst, .ost, .mbox, or .eml.
2. Mail format file: In computing, a mail file can refer to a file that defines the format of an email message. For example, the mailcap file is a configuration file that specifies how to handle different types of email attachments.
3. Mail merge file: In word processing, a mail file can refer to a file that contains a list of recipients and their corresponding data, which is used to create personalized documents using a mail merge feature.
4. Postal mail file: In a physical sense, a mail file can refer to a physical folder or container used to store and organize mail, such as a mailbox or a file cabinet.

If you're looking for a specific type of mail file, please let me know and I'll do my best to help!