arp?what's the problem like?
Can not surf the internet,there have lots of reasons,if the internet is slow,sometimes can't open a new page,if u r sharing the internet with others,maybe someone is downing.
If u can not connect to the internet,try and your password is correct,try to run cmd,then ipconfig,see whether have ip address.Check with your modem,make sure it's working.
But if u what other help u,try to descript your issues more clearly.