1. Click the Chrome menu on the browser toolbar.
2. Select Settings > Show advanced settings.
3. In the "Privacy" section, click Content settings.
4. In the dialog that appears, find the “Handlers” section:
To allow requests, select “Allow sites to ask to become default handlers for protocols.”
5. Click Manage handlers.
6. Use the drop-down menu next to a listed protocol to select the web service that should be used by default.