I'm connected to the internet, but I can't browse websites. HELP!?

I'm connected to our Wifi connection, but I can't access the internet. Other applications can connect, such as Frostwire, Magic Jack, Skype, Yahoo! Messenger, etc. But my browsers, Firefox and Google Chrome, can't access the internet. It always shows up with a "Webpage unavailable" whenever I... show more I'm connected to our Wifi connection, but I can't access the internet. Other applications can connect, such as Frostwire, Magic Jack, Skype, Yahoo! Messenger, etc. But my browsers, Firefox and Google Chrome, can't access the internet. It always shows up with a "Webpage unavailable" whenever I access sites. The weird thing is, it only happens during the night. Around 9:00 pm GMT+. Also, our smartphones can access and browse properly. I've tried "Netsh int ip reset resetlog.txt" and "Netsh winsock reset". It only helped a bit. I managed to open a few websites then BAM. Back to square one. Some help here?
Update: I managed to write this because it's still pretty early.
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