Windows
Step 1
Click the "Start" button in the lower left of the computer screen.
Step 2
Click the Search box and type "cmd" (without quotes). Press the "Enter" key.
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Step 3
Type "ipconfig" at the prompt in the pop-up Command window. Press "Enter."
Step 4
Write down the numbers and symbols listed next to "IPv4 Address" or "IPv6 Address." Usually there will be either an IPv4 or IPv6 address listed, but if there are both, either one will work. This number is your computer's IP address.
Step 5
Take down the number sequence next to "Default Gateway." This is your router's IP address.
............ go to settings then wifi , get to your advanced settings of the connection u want to connect to , make sure the ip addresses match, if not , correct them and it will fix your problem !