

重複の可能性ありですが質問してみます。  
rorのまったくの初心者ですがrubyとrailsをインストール後  
`rails new sample` とした後  
`rails s`を入力すると以下の結果となりlocalhost:3000を表示できません。

[code]

    c:\rails>rails s
    Usage:
      rails new APP_PATH [options]
    
    Options:
          [--skip-namespace], [--no-skip-namespace]            # Skip namespace (aff
    ects only isolated applications)
      -r, [--ruby=PATH]                                        # Path to the Ruby bi
    nary of your choice
                                                               # Default: C:/Ruby25-
    x64/bin/ruby.exe
      -m, [--template=TEMPLATE]                                # Path to some applic
    ation template (can be a filesystem path or URL)
      -d, [--database=DATABASE]                                # Preconfigure for se
    lected database (options: mysql/postgresql/sqlite3/oracle/frontbase/ibm_db/sqlse
    rver/jdbcmysql/jdbcsqlite3/jdbcpostgresql/jdbc)
                                                               # Default: sqlite3
          [--skip-yarn], [--no-skip-yarn]                      # Don't use Yarn for
    managing JavaScript dependencies
          [--skip-gemfile], [--no-skip-gemfile]                # Don't create a Gemf
    ile
      -G, [--skip-git], [--no-skip-git]                        # Skip .gitignore fil
    e
          [--skip-keeps], [--no-skip-keeps]                    # Skip source control
     .keep files
      -M, [--skip-action-mailer], [--no-skip-action-mailer]    # Skip Action Mailer
    files
      -O, [--skip-active-record], [--no-skip-active-record]    # Skip Active Record
    files
          [--skip-active-storage], [--no-skip-active-storage]  # Skip Active Storage
     files
      -P, [--skip-puma], [--no-skip-puma]                      # Skip Puma related f
    iles
      -C, [--skip-action-cable], [--no-skip-action-cable]      # Skip Action Cable f
    iles
      -S, [--skip-sprockets], [--no-skip-sprockets]            # Skip Sprockets file
    s
          [--skip-spring], [--no-skip-spring]                  # Don't install Sprin
    g application preloader
          [--skip-listen], [--no-skip-listen]                  # Don't generate conf
    iguration that depends on the listen gem
          [--skip-coffee], [--no-skip-coffee]                  # Don't use CoffeeScr
    ipt
      -J, [--skip-javascript], [--no-skip-javascript]          # Skip JavaScript fil
    es
          [--skip-turbolinks], [--no-skip-turbolinks]          # Skip turbolinks gem
    
      -T, [--skip-test], [--no-skip-test]                      # Skip test files
          [--skip-system-test], [--no-skip-system-test]        # Skip system test fi
    les
          [--skip-bootsnap], [--no-skip-bootsnap]              # Skip bootsnap gem
          [--dev], [--no-dev]                                  # Setup the applicati
    on with Gemfile pointing to your Rails checkout
          [--edge], [--no-edge]                                # Setup the applicati
    on with Gemfile pointing to Rails repository
          [--rc=RC]                                            # Path to file contai
    ning extra configuration options for rails command
          [--no-rc], [--no-no-rc]                              # Skip loading of ext
    ra configuration options from .railsrc file
          [--api], [--no-api]                                  # Preconfigure smalle
    r stack for API only apps
      -B, [--skip-bundle], [--no-skip-bundle]                  # Don't run bundle in
    stall
          [--webpack=WEBPACK]                                  # Preconfigure for ap
    p-like JavaScript with Webpack (options: react/vue/angular/elm/stimulus)
    
    Runtime options:
      -f, [--force]                    # Overwrite files that already exist
      -p, [--pretend], [--no-pretend]  # Run but do not make any changes
      -q, [--quiet], [--no-quiet]      # Suppress status output
      -s, [--skip], [--no-skip]        # Skip files that already exist
    
    Rails options:
      -h, [--help], [--no-help]        # Show this help message and quit
      -v, [--version], [--no-version]  # Show Rails version number and quit
    
    Description:
        The 'rails new' command creates a new Rails application with a default
        directory structure and configuration at the path you specify.
    
        You can specify extra command-line arguments to be used every time
        'rails new' runs in the .railsrc configuration file in your home directory.
    
        Note that the arguments specified in the .railsrc file don't affect the
        defaults values shown above in this help message.
    
    Example:
        rails new ~/Code/Ruby/weblog
    
        This generates a skeletal Rails installation in ~/Code/Ruby/weblog.
    
    c:\rails>cd sample
    
    c:\rails\sample>rails s
    Traceback (most recent call last):
            43: from bin/rails:4:in `<main>'
            42: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `require'
            41: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:253:in `load_dependency'
            40: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `block in require'
            39: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
            38: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
    
            37: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/loaded_features_index.rb:65:in `register'
            36: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_boot
    snap_lfi'
            35: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
            34: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /commands.rb:18:in `<top (required)>'
            33: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /command.rb:46:in `invoke'
            32: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /command/base.rb:65:in `perform'
            31: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor.rb:
    387:in `dispatch'
            30: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor/inv
    ocation.rb:126:in `invoke_command'
            29: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor/com
    mand.rb:27:in `run'
            28: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /commands/server/server_command.rb:142:in `perform'
            27: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /commands/server/server_command.rb:142:in `tap'
            26: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /commands/server/server_command.rb:145:in `block in perform'
            25: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `require'
            24: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:253:in `load_dependency'
            23: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `block in require'
            22: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
            21: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
    
            20: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/loaded_features_index.rb:65:in `register'
            19: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_boot
    snap_lfi'
            18: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
            17: from c:/rails/sample/config/application.rb:7:in `<top (required)>'
            16: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler.rb:114:in `requi
    re'
            15: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:65:in
     `require'
            14: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:65:in
     `each'
            13: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:76:in
     `block in require'
            12: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:76:in
     `each'
            11: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:81:in
     `block (2 levels) in require'
            10: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
             9: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
    
             8: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/loaded_features_index.rb:65:in `register'
             7: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_boot
    snap_lfi'
             6: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
             5: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sqlite3-1.3.13-x64-mingw
    32/lib/sqlite3.rb:2:in `<top (required)>'
             4: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sqlite3-1.3.13-x64-mingw
    32/lib/sqlite3.rb:6:in `rescue in <top (required)>'
             3: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `require'
             2: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:253:in `load_dependency'
             1: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `block in require'
    C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/bootsnap/load_path_cac
    he/core_ext/kernel_require.rb:32:in `require': cannot load such file -- sqlite3/
    sqlite3_native (LoadError)
    
    c:\rails\sample>gem install sqlite3
    Successfully installed sqlite3-1.3.13-x64-mingw32
    Parsing documentation for sqlite3-1.3.13-x64-mingw32
    Done installing documentation for sqlite3 after 1 seconds
    1 gem installed
    
    c:\rails\sample>rails s
    Traceback (most recent call last):
            43: from bin/rails:4:in `<main>'
            42: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `require'
            41: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:253:in `load_dependency'
            40: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `block in require'
            39: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
            38: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
    
            37: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/loaded_features_index.rb:65:in `register'
            36: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_boot
    snap_lfi'
            35: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
            34: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /commands.rb:18:in `<top (required)>'
            33: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /command.rb:46:in `invoke'
            32: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /command/base.rb:65:in `perform'
            31: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor.rb:
    387:in `dispatch'
            30: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor/inv
    ocation.rb:126:in `invoke_command'
            29: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor/com
    mand.rb:27:in `run'
            28: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /commands/server/server_command.rb:142:in `perform'
            27: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /commands/server/server_command.rb:142:in `tap'
            26: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/railties-5.2.1/lib/rails
    /commands/server/server_command.rb:145:in `block in perform'
            25: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `require'
            24: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:253:in `load_dependency'
            23: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `block in require'
            22: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
            21: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
    
            20: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/loaded_features_index.rb:65:in `register'
            19: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_boot
    snap_lfi'
            18: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
            17: from c:/rails/sample/config/application.rb:7:in `<top (required)>'
            16: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler.rb:114:in `requi
    re'
            15: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:65:in
     `require'
            14: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:65:in
     `each'
            13: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:76:in
     `block in require'
            12: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:76:in
     `each'
            11: from C:/Ruby25-x64/lib/ruby/site_ruby/2.5.0/bundler/runtime.rb:81:in
     `block (2 levels) in require'
            10: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
             9: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
    
             8: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/loaded_features_index.rb:65:in `register'
             7: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_boot
    snap_lfi'
             6: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/boots
    nap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
             5: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sqlite3-1.3.13-x64-mingw
    32/lib/sqlite3.rb:2:in `<top (required)>'
             4: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sqlite3-1.3.13-x64-mingw
    32/lib/sqlite3.rb:6:in `rescue in <top (required)>'
             3: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `require'
             2: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:253:in `load_dependency'
             1: from C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/activesupport-5.2.1/lib/
    active_support/dependencies.rb:287:in `block in require'
    C:/Ruby25-x64/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.2/lib/bootsnap/load_path_cac
    he/core_ext/kernel_require.rb:32:in `require': cannot load such file -- sqlite3/
    sqlite3_native (LoadError)
    
[/code]


CC BY-SA 4.0
2018-09-27T15:23:35.427
48773
2018-10-04T16:26:31.950
2018-09-27T16:24:43.353
19110
30259
question
ruby-on-rails
rubyonrailsのプロジェクトのブラウザ表示ができません