This is a known issue, it's not currently possible to connect to a PPPoE connection over wireless.
There are workarounds though: you can use wired to connect, say, for a first connection, than install and use pppoeconf, pon and poff to control PPPoE connections manually. See https://help.ubuntu.com/community/ADSLPPPoE for all the details on how to do this.
This is a known issue, it's not currently possible to connect to a PPPoE connection over wireless.
There are workarounds though: you can use wired to connect, say, for a first connection, than install and use pppoeconf, pon and poff to control PPPoE connections manually. See https:/ /help.ubuntu. com/community/ ADSLPPPoE for all the details on how to do this.