Just for other people diagnosing, I work for a company and install terminals for phone top up and credit cards, over the last month i've replaced loads of terminals due to lightning, this might help a little, it may be something simple like the adsl filter,the phone lead or the socket that it plugs into, examine the filter for any burnt residue... plug a normal phone into all the sockets to check for dial tone, now if all the sockets are live use that phone lead, unlpug all other phones and plug the router in direct with the good lead without filters to see if it sync's up. If it doesn't the router is damaged.