settings and make sure that :

1- under the connections that 'never dial up a connection' is the option.
2- your network connection [wireless or lan] is not having a static IP address and let your router assign that for you.
3- make sure that under LAN settings of your IE that you are not using a proxy server.
4- if it i connected and the strength is ok, this is on your laptop then it does not mean that the internet should be working on the router try opening Windows Command Prompt or CMD typr there this one:
ping [space, hit the space bar] then type any URL
Example:
ping goole.com

if you got a reply, then your internet is up but if you did not then the router is not configured properly ..

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