Xubuntu here, wireless has been working fine over multi distros and years on this machine, just ran the 15.04 upgrade last night. Now I have exactly the same problem: initially connects but drops almost immediately and can't reconnect, completely unusable.
$ lspci |grep -i network 04:06.0 Network controller: Ralink corp. RT2561/RT61 rev B 802.11g -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1444226 Title: [Kubuntu 15.04 beta] can't connect to wifi with Ralink RT2561/RT61 and NetworkManager To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1444226/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
