I have used my Roku 2 for years with no issues. Recently updated my Wi-Fi so need to reconnect my Roku device to the new internet however the remote has stopped working. I then bought a new remote and this also won't work/connect. I can't use the mobile app because the device needs to be connected to the same internet channel, but I can't connect to Wi-Fi without a remote!!
If the Roku 2 was the HD version the original remote was bluetooth, and if you purchased a new wifi-direct remote like the voice remote it won't work at all on the roku 2. It will take an IR remote in addition to the BT remote. So get a cheap universal remote with roku lsted.