Configure Alert on MD3220i

Hi there, I'm really in on pressure to configure Alert on MD3220i, please help me so I'm in rush. what I did so far:

I setup virtual mail server (include gmail account, it works fine I can send out test email) on my 2012 R2 server which is connected to SAN (just one volume)

I put different format of the mail server (server IP address, domain name, server name, Blank),  on Mail Server field, I don't know what format should I use. also put sender email address as I setup on virtual mail server and recipient email address too. depend on what name I put on Mail Server name I get different error like:

ServerName --> Validation unsuccessful. Input stream checking SMTP return code....

myVirtualMailServerName --> The mail (SMTP) server you specified can not be found ....

smtp.gmail.com --> Validation Unsuccessful . Incorrect return code from smtp command. ...

please help me to fix this one

thanks a lot