[ubuntu] How to rectify faulty network configuration?

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http://ubuntuforums.org – I connect to internet through modem. Recently I tried to look into the existing configuration but due to mistake, probably started a new pppoe configuration and aborted the process before completion. Can anybody please check from the /etc/network/interfaces given below if two pppoeconf are there and if it is so, how to rectify it? Code: auto lo iface lo inet loopback auto dsl-provider iface dsl-provider inet ppp pre-up /sbin/ifconfig eth0 up # line maintained by pppoeconf provider dsl-provider auto eth0 iface eth0 inet manual Thanks. (Hardware)