diff --git a/Library/Homebrew/cask/lib/hbc/cask_loader.rb b/Library/Homebrew/cask/lib/hbc/cask_loader.rb
index a0c44d9b41..43fd9080da 100644
--- a/Library/Homebrew/cask/lib/hbc/cask_loader.rb
+++ b/Library/Homebrew/cask/lib/hbc/cask_loader.rb
@@ -32,9 +32,9 @@ module Hbc
       end
 
       def load
-        raise CaskError, "'#{@path}' does not exist."  unless @path.exist?
-        raise CaskError, "'#{@path}' is not readable." unless @path.readable?
-        raise CaskError, "'#{@path}' is not a file."   unless @path.file?
+        raise CaskUnavailableError.new(@token, "'#{@path}' does not exist.")  unless @path.exist?
+        raise CaskUnavailableError.new(@token, "'#{@path}' is not readable.") unless @path.readable?
+        raise CaskUnavailableError.new(@token, "'#{@path}' is not a file.")   unless @path.file?
 
         @content = IO.read(@path)
 
@@ -45,7 +45,7 @@ module Hbc
 
       def cask(header_token, &block)
         if @token != header_token
-          raise CaskTokenDoesNotMatchError.new(@token, header_token)
+          raise CaskTokenMismatchError.new(@token, header_token)
         end
 
         Cask.new(header_token, sourcefile_path: @path, &block)
@@ -57,10 +57,11 @@ module Hbc
         ref.to_s.match?(::URI.regexp)
       end
 
+      attr_reader :url
+
       def initialize(url)
-        @url = url
-        uri = URI(url)
-        super Hbc.cache/File.basename(uri.path)
+        @url = URI(url)
+        super Hbc.cache/File.basename(@url.path)
       end
 
       def load
@@ -71,7 +72,7 @@ module Hbc
           ohai "Downloading #{@url}."
           curl @url, "-o", @path
         rescue ErrorDuringExecution
-          raise CaskUnavailableError, @url
+          raise CaskUnavailableError.new(@token, "Failed to download #{Formatter.url(@url)}.")
         end
 
         super
@@ -108,7 +109,7 @@ module Hbc
       end
 
       def load
-        raise CaskUnavailableError, @token
+        raise CaskUnavailableError.new(@token, "No Cask with this name exists.")
       end
     end
 
diff --git a/Library/Homebrew/cask/lib/hbc/cli.rb b/Library/Homebrew/cask/lib/hbc/cli.rb
index eec2788ec9..04a4149046 100644
--- a/Library/Homebrew/cask/lib/hbc/cli.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli.rb
@@ -166,7 +166,7 @@ module Hbc
       Hbc.default_tap.install unless Hbc.default_tap.installed?
       Hbc.init if self.class.should_init?(command)
       self.class.run_command(command, *args)
-    rescue CaskError, CaskSha256MismatchError, ArgumentError, OptionParser::InvalidOption => e
+    rescue CaskError, ArgumentError, OptionParser::InvalidOption => e
       msg = e.message
       msg << e.backtrace.join("\n").prepend("\n") if ARGV.debug?
       onoe msg
diff --git a/Library/Homebrew/cask/lib/hbc/cli/edit.rb b/Library/Homebrew/cask/lib/hbc/cli/edit.rb
index dec0fe36ba..77238d209e 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/edit.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/edit.rb
@@ -12,7 +12,7 @@ module Hbc
         cask_path = CaskLoader.path(cask_token)
 
         unless cask_path.exist?
-          raise CaskUnavailableError, %Q(#{cask_token}, run "brew cask create #{cask_token}" to create a new Cask)
+          raise CaskUnavailableError.new(cask_token, "Run #{Formatter.identifier("brew cask create #{cask_token}")} to create a new Cask.")
         end
 
         odebug "Opening editor for Cask #{cask_token}"
diff --git a/Library/Homebrew/cask/lib/hbc/cli/install.rb b/Library/Homebrew/cask/lib/hbc/cli/install.rb
index 4d0abc6775..4ac98d1deb 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/install.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/install.rb
@@ -31,14 +31,8 @@ module Hbc
           rescue CaskAlreadyInstalledError => e
             opoo e.message
             count += 1
-          rescue CaskAlreadyInstalledAutoUpdatesError => e
-            opoo e.message
-            count += 1
           rescue CaskUnavailableError => e
             self.class.warn_unavailable_with_suggestion cask_token, e
-          rescue CaskNoShasumError => e
-            opoo e.message
-            count += 1
           rescue CaskError => e
             onoe e.message
           end
@@ -51,9 +45,9 @@ module Hbc
         exact_match, partial_matches = Search.search(cask_token)
         error_message = e.message
         if exact_match
-          error_message.concat(". Did you mean:\n#{exact_match}")
+          error_message.concat(" Did you mean:\n#{exact_match}")
         elsif !partial_matches.empty?
-          error_message.concat(". Did you mean one of:\n")
+          error_message.concat(" Did you mean one of:\n")
                        .concat(Formatter.columns(partial_matches.take(20)))
         end
         onoe error_message
diff --git a/Library/Homebrew/cask/lib/hbc/cli/reinstall.rb b/Library/Homebrew/cask/lib/hbc/cli/reinstall.rb
index eb5f45c905..d90317892e 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/reinstall.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/reinstall.rb
@@ -17,9 +17,8 @@ module Hbc
             count += 1
           rescue CaskUnavailableError => e
             self.class.warn_unavailable_with_suggestion cask_token, e
-          rescue CaskNoShasumError => e
-            opoo e.message
-            count += 1
+          rescue CaskError => e
+            onoe e.message
           end
         end
 
diff --git a/Library/Homebrew/cask/lib/hbc/exceptions.rb b/Library/Homebrew/cask/lib/hbc/exceptions.rb
index b9d305a9ba..d9e1b07dbf 100644
--- a/Library/Homebrew/cask/lib/hbc/exceptions.rb
+++ b/Library/Homebrew/cask/lib/hbc/exceptions.rb
@@ -3,59 +3,43 @@ module Hbc
 
   class AbstractCaskErrorWithToken < CaskError
     attr_reader :token
+    attr_reader :reason
 
-    def initialize(token)
+    def initialize(token, reason = nil)
       @token = token
+      @reason = reason.to_s
     end
   end
 
   class CaskNotInstalledError < AbstractCaskErrorWithToken
     def to_s
-      "#{token} is not installed"
+      "Cask '#{token}' is not installed."
     end
   end
 
   class CaskUnavailableError < AbstractCaskErrorWithToken
     def to_s
-      "No available Cask for #{token}"
+      "Cask '#{token}' is unavailable" << (reason.empty? ? "." : ": #{reason}")
     end
   end
 
   class CaskAlreadyCreatedError < AbstractCaskErrorWithToken
     def to_s
-      %Q(A Cask for #{token} already exists. Run "brew cask cat #{token}" to see it.)
+      %Q(Cask '#{token}' already exists. Run #{Formatter.identifier("brew cask cat #{token}")} to edit it.)
     end
   end
 
   class CaskAlreadyInstalledError < AbstractCaskErrorWithToken
     def to_s
-      s = <<-EOS.undent
-        A Cask for #{token} is already installed.
-      EOS
-
-      s.concat("\n").concat(reinstall_message)
-    end
-
-    private
-
-    def reinstall_message
       <<-EOS.undent
+        Cask '#{token}' is already installed.
+
         To re-install #{token}, run:
-          brew cask reinstall #{token}
+          #{Formatter.identifier("brew cask reinstall #{token}")}
       EOS
     end
   end
 
-  class CaskAlreadyInstalledAutoUpdatesError < CaskAlreadyInstalledError
-    def to_s
-      s = <<-EOS.undent
-        A Cask for #{token} is already installed and using auto-updates.
-      EOS
-
-      s.concat("\n").concat(reinstall_message)
-    end
-  end
-
   class CaskCommandFailedError < CaskError
     def initialize(cmd, stdout, stderr, status)
       @cmd = cmd
@@ -84,8 +68,8 @@ module Hbc
   class CaskX11DependencyError < AbstractCaskErrorWithToken
     def to_s
       <<-EOS.undent
-        #{token} requires XQuartz/X11, which can be installed using Homebrew-Cask by running
-          brew cask install xquartz
+        Cask '#{token}' requires XQuartz/X11, which can be installed using Homebrew-Cask by running
+          #{Formatter.identifier("brew cask install xquartz")}
 
         or manually, by downloading the package from
           #{Formatter.url("https://www.xquartz.org/")}
@@ -101,60 +85,67 @@ module Hbc
 
   class CaskUnspecifiedError < CaskError
     def to_s
-      "This command requires a Cask token"
+      "This command requires a Cask token."
     end
   end
 
   class CaskInvalidError < AbstractCaskErrorWithToken
-    attr_reader :submsg
-    def initialize(token, *submsg)
-      super(token)
-      @submsg = submsg.join(" ")
-    end
-
     def to_s
-      "Cask '#{token}' definition is invalid#{": #{submsg}" unless submsg.empty?}"
+      "Cask '#{token}' definition is invalid" << (reason.empty? ? ".": ": #{reason}")
     end
   end
 
-  class CaskTokenDoesNotMatchError < CaskInvalidError
+  class CaskTokenMismatchError < CaskInvalidError
     def initialize(token, header_token)
-      super(token, "Bad header line: '#{header_token}' does not match file name")
+      super(token, "Token '#{header_token}' in header line does not match the file name.")
     end
   end
 
-  class CaskSha256MissingError < ArgumentError
-  end
+  class CaskSha256Error < AbstractCaskErrorWithToken
+    attr_reader :expected, :actual
 
-  class CaskSha256MismatchError < RuntimeError
-    attr_reader :path, :expected, :actual
-    def initialize(path, expected, actual)
-      @path = path
+    def initialize(token, expected = nil, actual = nil)
+      super(token)
       @expected = expected
       @actual = actual
     end
+  end
+
+  class CaskSha256MissingError < CaskSha256Error
+    def to_s
+      <<-EOS.undent
+        Cask '#{token}' requires a checksum:
+          #{Formatter.identifier("sha256 '#{actual}'")}
+      EOS
+    end
+  end
+
+  class CaskSha256MismatchError < CaskSha256Error
+    attr_reader :path
+
+    def initialize(token, expected, actual, path)
+      super(token, expected, actual)
+      @path = path
+    end
 
     def to_s
       <<-EOS.undent
-        sha256 mismatch
-        Expected: #{expected}
-        Actual: #{actual}
-        File: #{path}
+        Checksum for Cask '#{token}' does not match.
+
+        Expected: #{Formatter.success(expected.to_s)}
+        Actual:   #{Formatter.error(actual.to_s)}
+        File:     #{path}
+
         To retry an incomplete download, remove the file above.
       EOS
     end
   end
 
-  class CaskNoShasumError < CaskError
-    attr_reader :token
-    def initialize(token)
-      @token = token
-    end
-
+  class CaskNoShasumError < CaskSha256Error
     def to_s
       <<-EOS.undent
         Cask '#{token}' does not have a sha256 checksum defined and was not installed.
-        This means you have the "--require-sha" option set, perhaps in your HOMEBREW_CASK_OPTS.
+        This means you have the #{Formatter.identifier("--require-sha")} option set, perhaps in your HOMEBREW_CASK_OPTS.
       EOS
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/installer.rb b/Library/Homebrew/cask/lib/hbc/installer.rb
index 7da9731e51..aa6d600f7f 100644
--- a/Library/Homebrew/cask/lib/hbc/installer.rb
+++ b/Library/Homebrew/cask/lib/hbc/installer.rb
@@ -94,7 +94,6 @@ module Hbc
       odebug "Hbc::Installer#install"
 
       if @cask.installed? && !force? && !@reinstall
-        raise CaskAlreadyInstalledAutoUpdatesError, @cask if @cask.auto_updates
         raise CaskAlreadyInstalledError, @cask
       end
 
@@ -143,7 +142,7 @@ module Hbc
     def verify_has_sha
       odebug "Checking cask has checksum"
       return unless @cask.sha256 == :no_check
-      raise CaskNoShasumError, @cask
+      raise CaskNoShasumError, @cask.token
     end
 
     def verify
diff --git a/Library/Homebrew/cask/lib/hbc/verify/checksum.rb b/Library/Homebrew/cask/lib/hbc/verify/checksum.rb
index d079a44464..620703d313 100644
--- a/Library/Homebrew/cask/lib/hbc/verify/checksum.rb
+++ b/Library/Homebrew/cask/lib/hbc/verify/checksum.rb
@@ -33,13 +33,13 @@ module Hbc
       end
 
       def verify_checksum
-        raise CaskSha256MissingError, "sha256 required: sha256 '#{computed}'" if expected.nil? || expected.empty?
+        raise CaskSha256MissingError.new(cask.token, expected, computed) if expected.nil? || expected.empty?
 
         if expected == computed
           odebug "SHA256 checksums match"
         else
           ohai 'Note: running "brew update" may fix sha256 checksum errors'
-          raise CaskSha256MismatchError.new(downloaded_path, expected, computed)
+          raise CaskSha256MismatchError.new(cask.token, expected, computed, downloaded_path)
         end
       end
     end
diff --git a/Library/Homebrew/test/cask/cli/install_spec.rb b/Library/Homebrew/test/cask/cli/install_spec.rb
index b1b26c8675..0720d0d775 100644
--- a/Library/Homebrew/test/cask/cli/install_spec.rb
+++ b/Library/Homebrew/test/cask/cli/install_spec.rb
@@ -41,7 +41,7 @@ describe Hbc::CLI::Install, :cask do
 
     expect {
       Hbc::CLI::Install.run("local-transmission")
-    }.to output(/Warning: A Cask for local-transmission is already installed./).to_stderr
+    }.to output(/Warning: Cask 'local-transmission' is already installed./).to_stderr
   end
 
   it "allows double install with --force" do
@@ -80,7 +80,7 @@ describe Hbc::CLI::Install, :cask do
       rescue Hbc::CaskError
         nil
       end
-    }.to output(/No available Cask for localcaffeine\. Did you mean:\nlocal-caffeine/).to_stderr
+    }.to output(/Cask 'localcaffeine' is unavailable\. Did you mean:\nlocal-caffeine/).to_stderr
   end
 
   it "returns multiple suggestions for a Cask fragment" do
@@ -90,7 +90,7 @@ describe Hbc::CLI::Install, :cask do
       rescue Hbc::CaskError
         nil
       end
-    }.to output(/No available Cask for local-caf\. Did you mean one of:\nlocal-caffeine/).to_stderr
+    }.to output(/Cask 'local-caf' is unavailable\. Did you mean one of:\nlocal-caffeine/).to_stderr
   end
 
   describe "when no Cask is specified" do
diff --git a/Library/Homebrew/test/cask/dsl_spec.rb b/Library/Homebrew/test/cask/dsl_spec.rb
index 7eeabcf494..5849f581b0 100644
--- a/Library/Homebrew/test/cask/dsl_spec.rb
+++ b/Library/Homebrew/test/cask/dsl_spec.rb
@@ -57,7 +57,7 @@ describe Hbc::DSL, :cask do
       it "raises an error" do
         expect {
           cask
-        }.to raise_error(Hbc::CaskTokenDoesNotMatchError, /Bad header line:.*does not match file name/)
+        }.to raise_error(Hbc::CaskTokenMismatchError, /header line does not match the file name/)
       end
     end
 
diff --git a/Library/Homebrew/test/cask/installer_spec.rb b/Library/Homebrew/test/cask/installer_spec.rb
index a32f71cabe..8ef82c1d59 100644
--- a/Library/Homebrew/test/cask/installer_spec.rb
+++ b/Library/Homebrew/test/cask/installer_spec.rb
@@ -145,22 +145,6 @@ describe Hbc::Installer, :cask do
       expect(with_macosx_dir.staged_path.join("__MACOSX")).not_to be_a_directory
     end
 
-    it "installer method raises an exception when already-installed Casks which auto-update are attempted" do
-      with_auto_updates = Hbc::CaskLoader.load_from_file(TEST_FIXTURE_DIR/"cask/Casks/auto-updates.rb")
-
-      expect(with_auto_updates).not_to be_installed
-
-      installer = Hbc::Installer.new(with_auto_updates)
-
-      shutup do
-        installer.install
-      end
-
-      expect {
-        installer.install
-      }.to raise_error(Hbc::CaskAlreadyInstalledAutoUpdatesError)
-    end
-
     it "allows already-installed Casks which auto-update to be installed if force is provided" do
       with_auto_updates = Hbc::CaskLoader.load_from_file(TEST_FIXTURE_DIR/"cask/Casks/auto-updates.rb")
 
diff --git a/Library/Homebrew/test/cask/verify/checksum_spec.rb b/Library/Homebrew/test/cask/verify/checksum_spec.rb
index 55c0e5f440..4b8543d2b4 100644
--- a/Library/Homebrew/test/cask/verify/checksum_spec.rb
+++ b/Library/Homebrew/test/cask/verify/checksum_spec.rb
@@ -1,5 +1,5 @@
 describe Hbc::Verify::Checksum, :cask do
-  let(:cask) { double("cask") }
+  let(:cask) { double("cask", token: "cask") }
   let(:downloaded_path) { double("downloaded_path") }
   let(:verification) { described_class.new(cask, downloaded_path) }