I had the same issue with my cannon printer. Since you cannot enter the password on the model itself because cannon printers do not allow alphabetical characters if you utilize them on your password, you will have to use the WIP button on your router. First begin WIP set up your cannon printer then locate WIP button on router press and hold till it blinks and then your done. Just a heads up, set up may differ slightly depending on model. As for Roku, I currently dont own one but you may be able to set up this way if it supports WIP.
