Email via Gmail not Outlook Issue

Email via Gmail not Outlook Issue

Hello, 

I have setup my Gmail integration with Zoho and I can now view my emails within Zoho. However, when I am in an account or contact and click on their email, I get a window telling me that Outlook is not setup. 

Why if Gmail is set up and activated would it be telling me that Outlook is required? 

Any assistance appreciated. 

Jaques