PPTP connection didn't work till I uninstalled Comodo Firewall

Comodo Internet Security - CIS Firewall Help - CIS
#1

I was fixing my friends pc and he uses a pptp vpn. I couldn’t make it work until I uninstalled Comodo Firewall.

Why is that?

Is there a setting that I can change to make it work?

#2

See if this helps.