If you have more than one Gmail address and you want to change which email is the default mailto: for CRM please find some information below to show you how to do this:

How to Change Your Default E-Mail Address in GMail

  1. Click the Settings icon in the top right corner of your gmail account user interface.
  2. Select Mail Settings from the drop-down menu.
  3. Click the Accounts and Import tab at the top of the Settings menu.
  4. In the Send Mail As sectionclick the Make Default link next to the e-mail address you want to always send e-mails from in your gmail account.
  5. In the When Replying to a Message section below, select the email address you wish to permanently reply to e-mails from (regardless of the e-mail address that the e-mail was originally sent to)
  6. To save these preferences, click the General tab at the top of the Settings menu.
  7. Scroll down to the Save Changes button at the bottom of the Settings menu.

By doing the above you would have set up your preferred gmail address to be your default email when sending out emails.