error code 721 - 718

[gsr600]

as above - i have had a lot of difficulty getting the internet this week,
1 day tried i logging on about 20 times after rebooting computer/ checking plugs /cables etc,
error code721 - could this be computer related - as it said my modem connection was OK -
phone line was working - as for trying to get through to talk talk was useless,
is there a free fix download (apart from regcure) which i tried on another system years ago,
or shall i just get a new computer - as this one has already cost me £175 in repairs in the past year.
T.I.A.

[Wak]

Borrow another computer and google for "Error Code 721"
MS explains the possible problem and offers a downloadable tool to repair the Error.
Could be bad wiring or missing file.
Put the tool on a memory stick and load into the duff computer.
Worth a try?