I cannot ping to the RE200 ( no response). Acer Dell

I reinstalled a computer back to windows 8.1 pro 64 bit, it worked very well with RE200. My android smartphones and tablets also work fine with the RE200. What should I do next ?

I set all of my computer with static IP. I also have tried to set the SSID of the re200 to the same and different to the main router, but it didn't work when it connected to the re200.

Model : AC750 WiFi Range Extender Model No. RE200 Hardware Version : RE200 v1 00000000 Firmware Version : 3.14.2 Build 150514 Rel.38108n ISP : I have 3 computers, DELL, ACER and Lenovo. All of them...