Google Chrome
Open your Chrome web browser.
Click the Chrome menu icon in the top right-hand corner of the window.
Click Settings.
Click Show Advanced Settings at the bottom of the page.
Under "Privacy," click Content Settings.
Scroll down to the "Handlers" section, and click the Manage Handlers button.
Select your desired, default email client (e.g. Gmail).
Firefox
Open your Firefox web browser.
Click the Firefox menu the top left-hand corner of the window.
Click Options (PC) or Preferences (Macintosh).
Click the Applications subtab.
Use the search bar for "mailto."
Click the drop-down menu under the "Action" column.
Select your desired, default email client (e.g. Use Gmail).
Click OK. (Note: On a Macintosh computer, your settings will automatically be saved, so you will not need to click OK.)