I connect to Openvpn (that runs on my raspberry pi 3, installed using pivpn script) using android phone. Everything works out of the box except my email client. I use BlueMail app and I have my email account on yahoo.com. App can't connect to yahoo server and thus check my emails.
I didn't have to provide email server settings manually since BlueMail has done all configuration automatically. On Yahoo webpage I checked that IMAP protocol is setup on port 993.
sudo iptables -Son my pi returns:
-P INPUT ACCEPT
-P FORWARD ACCEPT
-P OUTPUT ACCEPT
sudo iptables -L on my pi returns:
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Any idea where should I look for resolution of this problem?