FIRST, u should try another net port and another wire to check whether there r sth wrong with the devices.
SECOND, it is ur pc's problem if first one do not give u a satisfied result, so the reason may be u have installed some softwares which r not fittable with ur pc's hardwares or other softwares related with web connection. So i recommend u restore ur pc to some days ago, when ur pc do worked well. the system restore is located at (START=>ALL PROGRAMS=>ACCESSORIES=>SYSTEM TOOLS=>SYSTEM RESTORE).
THIRD, if the second step still do not work (actually, it should work on most conditions), heheeeeeeeee, reinstall windows, i mean use recover CD given to u with ur pc when u bought it.
FORTH, throw ur pc out of ur window because no one can save it already. (this one is just joke~~)
^_^ REMARKS: what i said just now can be used only at windows XP.....
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