SMTP on port 25 is blocked to prevent abuse. Web based emails like gmail and yahoo mail should still work. You should still be able to receive email with no issues.
Refer Protect Privacy with P2P and Torrents article in the knowledge base.
To force connect disable other servers in OpenVPN config by prefixing "remote" with "#" to read as follows # remote IP_Address Config can be opened in any text editor like notepad, textedit, etc.