There are a few things that can case this error, however the error message basically states that the vRanger server does not have access to the email server that was provided. Either the server name, the port, the network, the authentication, some link in the chain of communication is broken (see resolution).
The resolution(s) to this problem differ depending upon the environment. The things that
1) Port 25 not being enabled on the VLAN that is presented to the vRanger server.
2) Incorrect email server address entered.
3) Permissions not configured to allow vRanger to authenticate to the SMTP server.
4) Permissions not configured appropriately for the 'from' address to send emails on behalf of vRanger.
5) vRanger does not support POP3 and IMAP4 email accounts.
