I upgraded my Dell Inspiron 7547 from Ubuntu 14.10 to Ubuntu 15.04 today, and I am now unable to connect to wireless networks.
I can see the wireless connection I am trying to connect to, but I am unable to connect. The connection times out without presenting an error message. First I tried forgetting the network and putting the information back in manually. I then tried disabling the wireless security on the router (Linksys E900) and reconnecting and had the same issue. I also tried connecting to a WiFi hotspot from my phone and had the same issue. The wireless connection from the router works fine on Windows 8.1 and my other wireless devices.
Any advice on what I should try next? What additional information can I provide to help?
Per comment, here is the output from running the wireless script: http://pastebin.ubuntu.com/10875310/