A mailto behavior is to define how Windows handles a mailto link, mostly on the web pages, when it’s clicked. The default behavior can change every time when a new program gets installed into your system. It’s usually handled through the default mail application installed on your computer but you can change it to use different method.
In Windows 8, it’s by default set to use the native Mail Windows 8 app but here is how you can change it.
1. Open Control Panel. You can do so easily press Win+X, and select Control Panel from power user menu that pops up.