I can't install my ex6120

Maybe some more info on this might help. 

1. What firmware is on your EX6120

2. What router are you connecting it to? 

3. What installation process are you using? WPS, the app installtion, the installation assistant through the browser

4. Where is it failing? its tough to tell you whats going on off such limited info. What happens when you try, at what point does it fail, are you getting any error messages?

We're not there to see what you're doing/done so help us out a little and we can better assist you.