WiFi Internet connection problems with laptop

Hello
I have a fundamental problem
I was connected to the laptop modem
When I changed from Windows
But does not connect to the modem Internet
My laptop is connected to another modem
The problem is only with my modem
Smartphones and tablet computers, and no problem to connect to the modem and Internet access
This is the only laptop
My laptop does not connect to the modem, but Internet and Wi-Fi icon is a small yellow warning
Please help me
IP and DNS as I did, but I still was not right
Difficulty finding Windows does not work
Hellllllllllllllllllllllllllllllllp Meeeeeeeeeeeeeeeeee