If you use web mail like gmail or Yahoo then you will know that when you click on a mailto link on a webpage it tries to open an installed mail program such as Outlook.
There is a simple, free, open source, application available, GmailDefaultMaker that fixes this, so that webmail will be used for these links. It works for gmail, google apps, Yahoo, Hotmail, AOL and QQ Mail.
There are also instructions available if you want the app to setup a different webmail system.
Run the app once and the job is done, nothing left running in the background. I’ve used it on Windows 7, 32 bit and 64 bit OS with no problems.
For more info visit the website at http://gmaildefault.codeplex.com/