I recently got openvpn going on a PC in server mode. When openvpn was first set up it was on a different machine, and I use port 443 to allow access from work. I had port 80 forwarded to the machine with apache and 443 forwarded to the machine with openvpn.
Now I have apache and openvpn on the same machine. The machine of course has the tap connector bridged with the ethernet port to facilitate openvpn. I can display web pages on any machine on the same subnet by using
http://machine-name, but pages do not work externally while openvpn is running.
If the two services are going to conflict it would seem they would conflict the same, whether accessed through the subnet, or accessed from outside, through the router, and forwarded. Openvpn works OK. There is a bridge on the machine, so stuff coming into the machine comes through one IP address, that of the bridge, whether done from the same subnet or externally.
If anyone has an idea please let me know. Thanks