diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index 71127cb1..6db88aaa 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1,6 +1,6 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2024-01-23 14:26:06 UTC using RuboCop version 1.50.2.
+# on 2024-04-24 11:01:50 UTC using RuboCop version 1.50.2.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
@@ -50,7 +50,7 @@ Metrics/BlockLength:
 # Offense count: 12
 # Configuration parameters: CountComments, CountAsOne.
 Metrics/ClassLength:
-  Max: 330
+  Max: 333
 
 # Offense count: 53
 # Configuration parameters: AllowedMethods, AllowedPatterns.
@@ -103,15 +103,6 @@ Security/IoMethods:
   Exclude:
     - 'lib/puppet-debugserver/debug_session/break_points.rb'
 
-# Offense count: 5
-# This cop supports safe autocorrection (--autocorrect).
-# Configuration parameters: AllowedMethods, AllowedPatterns.
-# AllowedMethods: ==, equal?, eql?
-# Style/ClassEqualityComparison:
-#   Exclude:
-#     - 'lib/puppet-languageserver/manifest/definition_provider.rb'
-#     - 'lib/puppet-languageserver/manifest/signature_provider.rb'
-
 # Offense count: 104
 # Configuration parameters: AllowedConstants.
 Style/Documentation:
diff --git a/lib/puppet-languageserver/message_handler.rb b/lib/puppet-languageserver/message_handler.rb
index 0b753974..6265630d 100644
--- a/lib/puppet-languageserver/message_handler.rb
+++ b/lib/puppet-languageserver/message_handler.rb
@@ -300,9 +300,12 @@ def notification_initialized(_, _json_rpc_message)
       # Raise a warning if the Puppet version is mismatched
       server_options = protocol.connection.server.server_options
       unless server_options[:puppet_version].nil? || server_options[:puppet_version] == Puppet.version
-        json_rpc_handler.send_show_message_notification(
-          LSP::MessageType::WARNING,
-          "Unable to use Puppet version '#{server_options[:puppet_version]}' as it is not available. Using version '#{Puppet.version}' instead."
+        protocol.encode_and_send(
+          ::PuppetEditorServices::Protocol::JsonRPCMessages.new_notification(
+            'window/showMessage',
+            'type' => LSP::MessageType::WARNING,
+            'message' => "Unable to use Puppet version '#{server_options[:puppet_version]}' as it is not available. Using version '#{Puppet.version}' instead."
+          )
         )
       end
 
diff --git a/spec/languageserver/unit/puppet-languageserver/message_handler_spec.rb b/spec/languageserver/unit/puppet-languageserver/message_handler_spec.rb
index 6c2f9570..52a1bcfd 100644
--- a/spec/languageserver/unit/puppet-languageserver/message_handler_spec.rb
+++ b/spec/languageserver/unit/puppet-languageserver/message_handler_spec.rb
@@ -881,6 +881,40 @@ def client_cap_hash(client_cap_string, dynamic_reg)
       )
     end
 
+    describe 'PuppetLanguageServer::MessageHandler' do
+      let(:server_options) { { puppet_version: '5.5.1' } }
+      let(:server) { double('PuppetEditorServices::Server') }
+      let(:connection) { double('PuppetEditorServices::Protocol::Connection', id: 'some_id') }
+      let(:protocol) { double('PuppetEditorServices::Protocol::JsonRPC') }
+      let(:handler_object) { PuppetLanguageServer::MessageHandler.new(protocol) }
+    
+      before do
+        allow(server).to receive(:server_options).and_return(server_options)
+        allow(connection).to receive(:server).and_return(server)
+        allow(protocol).to receive(:connection).and_return(connection)
+      end
+    
+      context 'When receiving a notification' do
+        context '.notification_initialized' do
+          it 'sends a warning message when Puppet versions are mismatched' do
+            allow(Puppet).to receive(:version).and_return('6.0.0')
+          
+            expected_message = {
+              'type' => LSP::MessageType::WARNING,
+              'message' => "Unable to use Puppet version '#{server_options[:puppet_version]}' as it is not available. Using version '#{Puppet.version}' instead."
+            }
+          
+            expect(protocol).to receive(:encode_and_send) do |arg|
+              expect(arg).to be_a(PuppetEditorServices::Protocol::JsonRPCMessages::NotificationMessage)
+              expect(arg.params).to eq(expected_message)
+            end
+          
+            handler_object.notification_initialized(nil, nil)
+          end
+        end
+      end
+    end
+
     # initialized - https://github.com/Microsoft/language-server-protocol/blob/master/protocol.md#initialized
     describe '.notification_initialized' do
       let(:notification_method) { 'initialized' }