Cannot use OpenVPN over Sprint Mobile but works on Wi-Fi

[jeffshead]

I have an HTC EVO 4G LTE through Sprint.

I installed and configured OpenVPN to work with Sophos SSL VPN. It works fine when I have a Wi-Fi connection on the phone but it does not work with the mobile 3G or 4G connection. When I try to use OpenVPN with a 3G or 4G connection, OpenVPN makes the connection but I cannot access the Internet.

I don't know where to begin troubleshooting or what other info is required from me in order to receive help from this forum.

Can someone help me, please?

[jeffshead]

I think I found the solution.

I checked the "Override DNS Settings by Server" option.

Is this secure and what is "searchDomain" used for? Right now it is defaulted to: blinkt.de