[トラブル] RailsでThe page you were looking for doesn't exist

Ruby on RailsでController追加時に
The page you were looking for doesn't exist
のエラーが出てしまう場合の原因と対処方法を紹介。

config/routes.rbの設定が間違っている

下の書き方をすれば動くはず。

get '(URIパターン)' => '(拡張子を抜いたcontrollerファイル名)#(メソッド名)'