1.First connect your pc or laptop with a wire to the lan port of ptcl modem.
2.now chek if internet is working fine.then open browser and write 192.168.1.1 in the address bar then username=admin paswd=admin or whatever u set.
3.Go to left side menu To The advanced setup then in LAN chek whether your dhcp is enable or not .if enable then write as start ip=192.168.1.2 end ip=192.168.1.254. then go nat option chek it enable or not if not then enable it.
4.now disconect the wire from ptcl modem . connect wire from lan port of witribe device.
Go to control panel then metwork and internet connection then double click on local area netwk then click on support at top and then click details then chek if you are getting ip from same subnet i.e of ptcl modem 192.168.1.x or not if not then just not the gateway of this device and place it in your browser .by default it should be 192.168.15.1.then write password wimax or witribe or whatever u set.
5.then go to Lan setting type option then please change its lan ip=to 192.168.1.4 subnet mask=255.255.255.0 then
6.now go to Dhcp option of the device and just disable it .
Second phase :
1. Now please turn on ptcl DSL modem . now take a patch cable rj-45 if u have otherwise buy it .it is easily available from computer accessories shop .Then connect it from lan port of ptcl modem to witribe device lan port.
2.Now turn on ur laptop and search wireless connection . Now u will find ur witribe device connect it and ur internet will work