My MacBook can't connect to my wifi where it used to before

This solution assumes that you already tried Network Diagnostic (Open System Preferences->Assist Me->Diagnostics) solution but still f...

This solution assumes that you already tried Network Diagnostic (Open System Preferences->Assist Me->Diagnostics) solution but still failed to connect to your wireless device. What's more confusing is that you used to connect to this wireless device before and was even surfing the web last night. And worst is that you can connect your other laptop to it :-)

There are many common connection problems like security type incompatibility, distance of your macbook to your device, etc. But in my case the problem was the DNS. I'm always using google dns: 8.8.8.8 and 8.8.4.4, but it failed me. So what I did was use another DNS provider (OpenDNS) 206.67.222.220.

Here's how:

1. Open System Preferences
2. Select Network
3. Click Advanced and open the DNS tab.
4. Add Open DNS and click Ok.

5.) Turn wifi off and then on and try to connect.