Security Permissions issue when installing...

Question

I'm trying to install a certificate file provided by my Company's helpdesk to configure a server source on Gigabyte gsmart i128 PDA for downloading my official mails into gsmart i128. When I click on file it states "You are about to install x*x, a certificate file issued by yyy. Do you want to continue? On clicking "Yes", it gives error message "Security Permission was insufficient to update your device". Please assist on how to install this certificate.