Error in Starting Database Mirroring

Hai Everyone.. I have an issue in mirroring which i described below.

I am getting the above error when i click on "start mirroring" button. I turned off firewall in my antivirus. 

And i also executed the below script in both my principal and mirror server. Because i created both the instances in my system only. And i am accessing those instances with windows authentication.

-- Thanks and Regards Srikar Reddy Gondesi, Trainee SQL Server Database Administrator Miracle Software systems, Inc.