Yahoo! Messenger is a popular advertisement-supported instant messaging client and associated protocol provided by Yahoo!. Yahoo! Messenger is provided free of charge and can be downloaded and used with a generic "Yahoo! ID" that also allows access to other Yahoo! services, such as Yahoo! Mail, where users can be automatically notified when they receive new email. Yahoo! also offers PC-PC, PC-Phone and Phone-to-PC service, file transfers, webcam hosting, text messaging service, and chat rooms in various categories.

In addition to instant messaging features similar to those offered by ICQ, it also offers (on Microsoft Windows) features such as: IMVironments (customizing the look of Instant Message windows, some of which include authorized themes of famous cartoons such as Garfield or Dilbert), address-book integration and Custom Status Messages. It was also the first major IM client to feature BUZZing and music-status. A further recently added feature is customized avatars.

Yahoo! Messenger 2.5.3 for Mac, released in 2003, is the current non beta release for Mac OS X. It has far fewer features than the current Windows release and has been reported to be quite buggy. 2.5.3 was also the very last release to support Classic (Mac OS 8.6-9.2.2) operating system. In June of 2006 Messenger for Mac 3.0b1 (build 17006) was released as a beta. This beta had a more modern interface than 2.5.3 and includes non-animated avatars,display image viewing, and some other features comparable to those on the Windows version. However, it still lacked the more advanced features contained in the Windows version, such as PC-to-PC calling, photo sharing, integrated address book, and chat rooms. Beta 1 received a refresh a month later (build 18274) which patched some serious connection issues and added reconnect when disconnected, but then remained unupdated for over a year. Yahoo! Messenger for Mac 3.0 beta 2 build 65474, released September 06, 2007, finally brought chat room support to the mac user as well as supported even more improved interface, tabs, and fixed the infamous scroll issue for users who had Safari 3/Webkit 522+ installed. However, due to unforeseen trouble implementing call feature, that ended up being cut from beta 2 near the last minute. Also, support for Mac OS X 10.0-10.3.9 was dropped in beta 2 based on a poll taken by Yahoo! to determine if beta releases should come out faster with less OS support, or slower with more. The latest beta version, 3.0b2 build 78326 (released November 21st, 2007), is required for Leopard (Mac OS X 10.5) users because the previous beta 2 releases (builds 65474 and 75170) were unstable under 10.5.x. Each revision of beta 2 has improved upon the Chat interface with extra UI tweaks and features based on feedback sent in on blog and email feedback forms.

There is a version of Yahoo! Messenger for Linux, available from Yahoo as an rpm package for Redhat or as a deb package for Debian. However, being a binary-only package, it works only with Linux on Intel/AMD processors. General-purpose messaging clients, such as GAIM, also work with Yahoo! Messenger.

On December 5, 2007, Yahoo! Messenger announces the release of Yahoo Messenger for Windows Vista as a Beta Release. It includes transparent Glass Windows and a new skin and GUI for the Windows Sidebar and program. Also integrated new tabs for going between different chat windows.

On October 29, 2007, Yahoo! Messenger announced the release of Yahoo! Messenger 9 Beta. It features a new and improved interface, new emoticons (also hidden emotions), the integration with Flickr account and a new in-line media player which enables the user to view maps, photos and videos from sites like Yahoo! Video and YouTube right in the IM window.

Yahoo! has announced a partnership with Microsoft to join their instant messaging networks. This would make Yahoo! Messenger compatible with Microsoft's .NET Messenger Service. It also made Microsoft's Windows Live Messenger compatible with Yahoo!'s Network. This change has taken effect as of 2006-07-13 - Yahoo! Messenger has integrated instant messaging with Windows Live Messenger users, and is fully functional.

British Telecommunications' BT Communicator software is based on Yahoo! Messenger. BT Communicator was withdrawn on 2006-12-31.

Yahoo! Messenger was originally launched under the name Yahoo! Pager on 1998-03-09.

Features

Yahoo! Voice

Main article: Yahoo! Voice

Yahoo! Voice is a Voice over IP PC-PC, PC-Phone and Phone-to-PC service , provided by Yahoo! via its Yahoo! Messenger instant messaging application. It is only available for the Windows platform.

Voicemail and file sharing

Yahoo! added voicemail and file sending capabilities to their client. File-sharing of sizes up to 1GB was added.

Plug-ins

As of 8.0, Yahoo! Messenger has added the ability for users to create plug-ins (via the use of the freely available Yahoo! Messenger Plug-in SDK), which are then hosted and showcased on the Yahoo! Plug-in gallery.

Yahoo! Mail integration

On July 2, 2007, Yahoo! plans to integrate Yahoo! Mail Beta and Yahoo! Messenger . Conversations will eventually be archived and stored in the same manner as emails. This allows users to search within their chat logs easily, and to have them centrally stored no matter what computer is used to have conversations.

Chat

All versions of Yahoo! Messenger have included the ability to access Yahoo! Chat rooms.

On June 19, 2005, with no advance warning, Yahoo! disabled users' ability to create their own chat rooms. The move came after KPRC-TV in Houston, Texas reported that many of the user-created rooms were geared toward pedophilia. Many regulars in these rooms used the rooms to set up meetings to have sex with children and trade lewd pictures. While it was thought this move came as a result of several advertisers pulling their ads from Yahoo!, a more likely cause was a $10 million lawsuit filed by watchdog groups of internet portals on behalf of a 12-year-old victim of molestation.

Yahoo! has since closed down the chat.yahoo.com site (which is now a redirect to a section of the Yahoo! Messenger page) because the great majority of chat users accessed it through Messenger. In August of 2007, it began requiring word verification in order to use Yahoo! Chat. Officially, this is to guard against spammers and automated bots, which had been a source of frustration for many chatters (This method has proved highly unsuccessful, as many rooms now have more bots than users). However, as this also logs users' IP addresses, this feature could presumably be used to monitor against the type of behavior that prevailed in the pedophilia-oriented rooms. The company claims to be still working on a way to allow users to create their own rooms while providing safeguards against abuse.

URI scheme

Yahoo! Messenger's installation process automatically installs an extra URI scheme ("protocol") handler into some web browsers, so that URIs beginning "ymsgr:" can open a new Yahoo! Messenger window with specified parameters. This is similar in function to the mailto: URI scheme, which creates a new e-mail message using the system's default mail program. For instance, a web page might include a link like the following in its HTML source to open a window for sending a message to the YIM user notarealuser:

To specify a message body, the m parameter is used, so that the link location might look like this:

Offline messaging

Offline messaging, a feature long offered by Yahoo!, allows online users to send messages to their contacts, even if said contacts are not signed in at the time. The sender's offline contacts will receive these messages when they next go online.

Interoperability

On October 13, 2005, Yahoo! and Microsoft announced plans to introduce interoperability between their two messengers, creating the second largest instant messenger userbase worldwide: 40 percent of all users (AIM currently holds 56 percent). The announcement comes after years of 3rd party interoperability success (most notably, Trillian, Pidgin) and criticisms that the major instant messengers were locking their networks. Microsoft has also had talks with AOL in an attempt to introduce further interoperability, but so far, AOL seems unwilling to participate.

Interoperability between Yahoo! and Windows Live Messenger was launched July 12, 2006. This allows, for Yahoo! and Windows Live Messenger users to chat to each other without the need to create an account on the other service, provided both contacts use the latest versions of the clients. For now, it's very hard to talk using the voice service among both messengers.

Games

There are various games and applications available that can be accessed via the conversation window by clicking the games icon and challenging your current contact.

Main process

yahoomessenger.exe is the main process belonging to the Yahoo! Instant Messenger application, an Internet messaging program. The name of the Yahoo! instance messaging client changed from ypager.exe to yahoomessenger.exe since version 7.5.0 Beta.

This applies to the Windows version of Yahoo! Messenger.

Upcoming releases

Yahoo! recently released a a preview version of Yahoo! Messenger for Windows Vista. It has been designed to exploit the new design elements of Vista's Windows Presentation Foundation.

The Mac OS X client version 3.0 Beta 2 has been released: file transfers have been re-enabled as have group conferences.

The Windows client version 9.0 Beta has been released. It supports both Windows XP and Vista. It features an improved interface and several new features.

The Windows Vista Beta version 1.0 has been released. It supports only Windows Vista and entitles a whole new user interface and features. It lacks basic function such as file transfer and webcam.

Latest releases

A screenshot of Yahoo! Messenger 3.0b1 for Mac OS X

Windows - 9.0.0.922

Windows Vista - 1.0 build 2008.01.11.428

Mac OS X - 3.0 beta 2 (build 78326) / November 21, 2007

Several third-party clients exist that can connect to the Yahoo! Messenger network, such as, Fire, Adium and Proteus. Adium can access the chat rooms, the others can't - they are for instant messaging only. Given Yahoo!'s apparent lack of interest in updating Messenger for Macintosh, many of these third-party clients actually have more features and are less buggy than Yahoo!'s product.

Unix - 1.0.4 / September 2003

The Unix version looks different from the Windows version.

Version 1.0.6.1 is available for Gentoo Linux (masked as ~x86).

Version 1.0.6 can be downloaded from the Unix Beta page: http://public.yahoo.com/~mmk/

Feature and release history

Windows

There are many versions between those listed here and prior to last version listed here. These are "major releases". See one of several sites listed in external links to find other, older versions of the product.

1.0 March 9, 1998

3.0 August 17, 2000

7.0.0.426 - August 8, 2005

Renamed to "Yahoo! Messenger with Voice"

Drag-and-drop photo sharing

Drag-and-drop file sharing

PC-to-PC calling

Voicemail

Ringtones

Yahoo! 360° integration

Pop-up Contact Cards

Spam Reporting

New tabs

New emoticons

Archive updates

LiveWords (Beta)

7.0.0.437 - August 30, 2005

8.0.0.505 - June 20, 2006

Plugins possible

8.0.0.508 - July 13, 2006

Interoperability between Yahoo! and Windows Live Messenger contacts

8.0.0.701 - August 10, 2006

The release date signifies the release of a beta version. This is not clearly documented on the Yahoo site.

8.0.0.716 - September 15, 2006

8.1.0.195 - October 24, 2006

Renamed to "Yahoo! Messenger"

Ability to check for updates from the help menu

8.1.0.209 - December 4, 2006

Patched an ActiveX Control Buffer Overflow

8.1.0.239 - January 19, 2007

Improvements in voice quality and sign-in, fixes for minor bugs with Windows Vista

8.1.0.244 - March 14, 2007

8.1.0.249 - March 28, 2007

Patches a security flaw

8.1.0.401 - June 8, 2007

Fixes a vulnerability with the Webcam ActiveX control

8.1.0.402 - June 15, 2007

Fixes a buffer overflow in an ActiveX control

8.1.0.413 - July 17, 2007

8.1.0.416 - August 22, 2007

Changes to voice library for better Vista support. (Users can get voice in Windows Vista without using a proxy app anymore, provided they still install codec themselves)

Fix to two Cam exploits

8.1.0.419 - August 29, 2007

Two more security patches

8.1.0.421 - September 6, 2007

9.0.0.797 Beta - October 29, 2007

New beta release of Yahoo! Messenger. It provides an improved user interface.

Brand new skins and emoticons

Flickr integration in the photo sharing feature

New in-line media player

New features for voice calls

Unicode support for better international messaging.

9.0.0.907 Beta - November 7, 2007

Fixed issues with Windows Vista installation problem

Message formatting in the IM window

Compact list view enabled

9.0.0.922 Beta - December 18, 2007

Mac

2.5.3 - September 24, 2003

Chat

Webcam

Conference chat

3.0 beta 1 (build 17006) - June 28, 2006

New UI

Display Images

Avatars Support

Stealth Settings

Interoperability between Yahoo! and Windows Live Messenger contacts

YMSG14

Prior Releases - Undocumented

3.0 beta 1 revision 2 (build 18274) - July 13, 2006

Auto Reconnect

YMSG14 related bug fixes.

3.0 beta 2 (build 65474) - September 06, 2007

Tabbed IM windows

Chat rooms

Improved stability for webcam and file transfer

More emoticons

Message archiving

YMSG15

No voice calling

Fixed scrolling up issue when Safari 3/Webkit 522+ is installed.

3.0 beta 2 revision 2 (build 75170) - October 25, 2007

Improved stability and compatibility with Mac OS X Version 10.5 (Leopard)

Some small interface improvements, including a new Show/Hide Display Images button in the IM and chat room windows

Improved chat room layout, with the list of chatters in a left hand, scrollable panel with age/sex/location details available on hover (if the user is sharing his/her profile)

Contextual (right click) menu's added to chatroom adding support for finally viewing a persons cam who isn't on contact list who's in the room.

3.0 beta 2 revision 3 (build 78326) - November 21, 2007

Improved stability and compatibility with Mac OS X Version 10.5 (Leopard)

Crash Reporter now works under Leopard.

Improvements to the sign in process when you're behind a firewall.

Couple of crash bugs fixed.

Malware

Yahoo! Messenger (along with other networks such as Windows Live Messenger and AOL Instant Messenger) is often used as a conduit or "vector" for delivering malicious software such as spyware, viruses, worms, and trojans to unsuspecting computer users. The two methods used by hackers to deliver malware over the IM vector are (1) sending a file transfer with a virus-infected file, and (2) delivering a message with socially engineered content containing a web address (URL) containing active malicious code. Viruses and worms with colorful names such as W32.Yalove or W32/Spybot-MQ have been identified as targeting users of the Yahoo! Messenger network over the past few years.

The threat of infection by these two methods is substantial and growing. The IM Security Center, a collaboration between security companies and corporations, has tracked attacks over IM since 2003 and shows well over 1000 distinct attacks over the public IM networks. The first half of 2007 saw an 84% increase in IM attacks over the first half of 2006. While IM-specific attacks remain a small percentage of overall virus and malware threats, the continued growth in usage of IM, along with the rapid adoption of IM in the workplace (See Instant Messaging) make IM an attractive vector for hackers, and both individuals and companies must take precautions to avoid infection.

The most common method of delivering a malicious payload is the use of social engineering to construct a message that appears to be coming from a contact on the recipient's contact list. A socially engineered message is one that is written in a friendly, informal manner, that could easily be mistaken as coming from a friend. The message typically will say something like "Click here to see pics of me from vacation!" or "Is this you?" with a web address -- known as a "poison URL" -- for the recipient to click. Upon clicking the web address, the recipient is connected to a website containing active content, which is instantly downloaded to the recipient's computer. In most cases, the payload contains an installer, a number of hidden files containing text, and code which causes the same socially engineered message with poison URL to be sent to every contact on the contact list. When the message is sent to all contacts, the cycle starts again, as each contact believes they are receiving a message from a trusted friend. In this manner, IM-borne malware is capable of propagating very rapidly through company and external networks.

Worms and viruses are discovered on a regular basis by security companies, particularly by the three companies with IM-specific security products, Akonix Systems, FaceTime Communications, and Symantec. According to IM security researchers at Akonix, the number of new threats identified each month is 30 to 35, with a high of 88 in October, 2006.

Spam

Yahoo have been criticised for the amount of unsolicited messages being received and have been accused of having little effect in combating it. Larry Dignan of Zdnet described the spam as becoming 'insufferable'.

Compatible software

Adium

Agile Messenger

BitlBee

Centericq

Fire

imeem

IMVU

Jabberwocky

Kopete

MECA Messenger

meebo

Meetro

Miranda IM

Paltalk

Pidgin (formerly Gaim)

Proteus

Qnext

SIM

Trillian

Trillian Pro

Trillian Astra

Windows Live Messenger