UPDATE: Microsoft has clarified that Windows Live Messenger will not be switched off on 15 March, but that it will simply start its transition on that date. Ars Technica reports that the various Windows Live clients for Xbox and other systems will continue to work after that date, but will eventually be turned off too.
For internet users of a certain generation, today is a sad day.
Microsoft has announced it will start to switch off its ageing Windows Live Messenger service on 15 March.
The software was one of the first internet chat services to gain true mainstream adoption, particularly by teenagers, after its launch in 1999.
Originally named MSN Messenger, it was renamed in 2006.
It is still used by more than 300 million people, according to the BBC.
But after Microsoft purchased Skype in October 2011 for £5.3 billion, it has been increasingly clear that it's time was up.
In November 2012 Microsoft said Messenger would be turned off in the New Year, but did not give a date.
Now the company has announced via an email to Messenger users the service will be shut off starting in two months, after which users will be directed to update to Skype.
Microsoft has made tools available for Messenger users to merge their contacts with Skype, and there is also an "upgrade" button on the desktop version of the application. The app will then uninstall and replace itself with Skype.