Branding removal from outgoing Email

Hello - we use Avsat on 4 office PC’s and we use Google as primary email client. I notice an auto inserted notice at the base of the email that says:
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com

How do I remove this?
thank you
Bill

I see it looks like when we receive an email with attachment however forward or replaying keeps this intact and we would like to turn this option off. We use pro version and do not believe marketing other companies freely from paid product by thier software inserting of branding with link to company website.

thank you

found how to remove