There are actually two ways to accomplish this, unfortunately only one way works in both Windows XP and Windows Vista. If you follow the steps below you should be able to use the mailto links on a web page to email someone easily.

Using Yahoo Messenger

The first way to set Yahoo as your default email program is to install Yahoo Messenger. Yahoo Messenger can be download at http://messenger.yahoo.com. If its installed correctly it will set Yahoo as your default email application. You will need to install the Browser Services option to make this work properly. Without the browser services installed, you still cannot set Yahoo Mail as your default.

Once Yahoo Messenger is installed, follow these steps to set the default email program.

1) Open Control Panel
2) Double-click on Internet Options
3) Click on the Program tab
4) Select Yahoo Mail from the drop down list (as shown below)

5) Click Ok
6) Close Control Panel

Unfortunately, this procedure DOES NOT work with Windows Vista computers.

Using YAttach!

YAttach! is a free simple to install program developed by a fellow named Chris Wood. It was created to allow someone to attach files to Yahoo Mail but works great at opening Yahoo Mail with a new message window all filled out when you click a mailto link on a web page. YAttach works in Windows XP and Windows Vista.

Yattach! sets itself as the default email program in Windows and will work in Internet Explorer, Firefox, and other browsers. When you click on a mailto link you’ll see a window pop up similar to the one below, then it will open Yahoo Mail and create a new message with the To: field already filled in.

Sometimes, the program will appear to hang at the screen above instead of opening Yahoo Mail. This issue can be easily resolved by logging into Yahoo Mail and choosing the option to “keep me signed in”.

YAttach! is the easiest to use program to allow web based email programs the ability to send documents directly from your computer or intercept mailto links clicked on web pages.

Download YAttach!

There is also a program called GAttach! that accomplishes the same thing for Gmail. My only complaint about that version is that it creates a message in the drafts folder instead of opening a new message window. Because of that issue, I prefer the Gmail Notifier. During the installation of the Gmail Notifier be sure to check the box for “use for outgoing email”.