|To get to the router setup page in your web browser, remove the Range Extender and have just the router connected to your PC or laptop via ethernet cable, like it was before you bought the Range Extender.|
When the router is fully connected and working, type IP number you've been given.
For your information, the WPS button is disabled because that method of wireless setup does not work 99% of the time. It was one of those many good ideas in theory which don't work in practice. The manual method should always be used instead of WPS whatever make of hub or router you have. WPS is a waste of time.