Help problem vpn

Can you help?
I have a problem with a vpn type (L2TP IPSEC VPN) just istallo Comodo antivirus stops working (error impossible to encrypt data).
But vpn set (tipe Automatic) then try to start the connection but then rightly error.

Unistal comodo antivirus vpn type (L2TP IPSEC VPN)connect ok.

thanks in advance for your attention

Excuse me for having posted yesterday evening in section firewall instead of the correct Antivirus.
the problem however I rediscount after installing Comodo antivirus and resolvesunistal Comodo antivirus