Webopedia on Google+Webopedia on TwitterWebopedia on FacebookTech Bytes Blog
Main » TERM » T »


Pronounced tee-neff, and short for Transport Neutral Encapsulation Format, a proprietary format used by the Microsoft Exchange and Outlook e-mail clients when sending messages formatted as Rich Text Format (RTF). When Microsoft Exchange thinks that it is sending a message to another Microsoft e-mail client, it extracts all the formatting information and encodes it in a special TNEF block. It then sends the message in two parts - the text message with the formatting removed and the formatting instructions in the TNEF block. On the receiving side, a Microsoft e-mail client processes the TNEF block and re-formats the message.

Unfortunately, most non-Microsoft e-mail clients cannot decipher TNEF blocks. Consequently, when you receive a TNEF-encoded message with a non-Microsoft e-mail client, the TNEF part appears as a long sequence of hexadecimal digits, either in the message itself or as an attached file (usually named WINMAIL.DAT).

8 Agenda Apps to Help Students Stay Organized

Webopedia's student apps roundup will help you to better organize your class schedule and stay on top of assignments and homework. Read More »

List of Free Shorten URL Services

A URL shortener is a way to make a long Web address shorter. Try this list of free services. Read More »

Top 10 Tech Terms of 2015

The most popular Webopedia definitions of 2015. Read More »

Java Basics, Part 1

Java is a high-level programming language. This guide describes the basics of Java, providing an overview of syntax, variables, data types and... Read More »

Java Basics, Part 2

This second Study Guide describes the basics of Java, providing an overview of operators, modifiers and control Structures. Read More »

The 7 Layers of the OSI Model

The Open System Interconnection (OSI) model defines a networking framework to implement protocols in seven layers. Use this handy guide to compare... Read More »