diff --git a/config/settings.yml b/config/settings.yml
index ef73431f..fd56903c 100644
--- a/config/settings.yml
+++ b/config/settings.yml
@@ -1,6 +1,6 @@
 discourse_solved:
   solved_enabled:
-    default: true
+    default: false
     client: true
   show_who_marked_solved:
     default: false
@@ -59,4 +59,3 @@ discourse_solved:
   enable_solved_tags:
     type: tag_list
     default: ""
-
diff --git a/db/migrate/20250721192553_enable_solved_if_already_installed.rb b/db/migrate/20250721192553_enable_solved_if_already_installed.rb
new file mode 100644
index 00000000..0ac17dd8
--- /dev/null
+++ b/db/migrate/20250721192553_enable_solved_if_already_installed.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+class EnableSolvedIfAlreadyInstalled < ActiveRecord::Migration[7.2]
+  def up
+    installed_at = DB.query_single(<<~SQL)&.first
+      SELECT created_at FROM schema_migration_details WHERE version='20191209095548'
+    SQL
+
+    if installed_at && installed_at < 1.hour.ago
+      # The plugin was installed before we changed it to be disabled-by-default
+      # Therefore, if there is no existing database value, enable the plugin
+      execute <<~SQL
+        INSERT INTO site_settings(name, data_type, value, created_at, updated_at)
+        VALUES('solved_enabled', 5, 't', NOW(), NOW())
+        ON CONFLICT (name) DO NOTHING
+      SQL
+    end
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end
diff --git a/spec/components/composer_messages_finder_spec.rb b/spec/components/composer_messages_finder_spec.rb
index 944fa8b4..e5ad912f 100644
--- a/spec/components/composer_messages_finder_spec.rb
+++ b/spec/components/composer_messages_finder_spec.rb
@@ -10,7 +10,10 @@
     fab!(:topic)
     fab!(:post) { Fabricate(:post, topic: topic, user: Fabricate(:user)) }
 
-    before { SiteSetting.disable_solved_education_message = false }
+    before do
+      enable_current_plugin
+      SiteSetting.disable_solved_education_message = false
+    end
 
     it "does not show message without a topic id" do
       expect(
diff --git a/spec/components/post_revisor_spec.rb b/spec/components/post_revisor_spec.rb
index d35cb828..103af717 100644
--- a/spec/components/post_revisor_spec.rb
+++ b/spec/components/post_revisor_spec.rb
@@ -13,6 +13,8 @@
     category
   end
 
+  before { enable_current_plugin }
+
   it "refreshes post stream when topic category changes to a solved category" do
     topic = Fabricate(:topic, category: Fabricate(:category_with_definition))
     post = Fabricate(:post, topic: topic)
diff --git a/spec/integration/solved_spec.rb b/spec/integration/solved_spec.rb
index 9a65f764..7212cb82 100644
--- a/spec/integration/solved_spec.rb
+++ b/spec/integration/solved_spec.rb
@@ -7,7 +7,10 @@
   fab!(:user) { Fabricate(:trust_level_4) }
   let(:p1) { Fabricate(:post, topic: topic) }
 
-  before { SiteSetting.allow_solved_on_all_topics = true }
+  before do
+    enable_current_plugin
+    SiteSetting.allow_solved_on_all_topics = true
+  end
 
   describe "customer filters" do
     before do
diff --git a/spec/lib/first_accepted_post_solution_validator_spec.rb b/spec/lib/first_accepted_post_solution_validator_spec.rb
index 87bd0277..c31e5f87 100644
--- a/spec/lib/first_accepted_post_solution_validator_spec.rb
+++ b/spec/lib/first_accepted_post_solution_validator_spec.rb
@@ -3,6 +3,8 @@
 describe DiscourseSolved::FirstAcceptedPostSolutionValidator do
   fab!(:user_tl1) { Fabricate(:user, trust_level: TrustLevel[1], refresh_auto_groups: true) }
 
+  before { enable_current_plugin }
+
   context "when trust level is 'any'" do
     it "validates the post" do
       post = Fabricate(:post, user: user_tl1)
diff --git a/spec/lib/guardian_extensions_spec.rb b/spec/lib/guardian_extensions_spec.rb
index a3354b50..2200784e 100644
--- a/spec/lib/guardian_extensions_spec.rb
+++ b/spec/lib/guardian_extensions_spec.rb
@@ -10,7 +10,10 @@
 
   let(:guardian) { user.guardian }
 
-  before { SiteSetting.allow_solved_on_all_topics = true }
+  before do
+    enable_current_plugin
+    SiteSetting.allow_solved_on_all_topics = true
+  end
 
   describe ".can_accept_answer?" do
     it "returns false for anon users" do
diff --git a/spec/models/copy_solved_topic_custom_field_spec.rb b/spec/models/copy_solved_topic_custom_field_spec.rb
index 574f0496..71a47368 100644
--- a/spec/models/copy_solved_topic_custom_field_spec.rb
+++ b/spec/models/copy_solved_topic_custom_field_spec.rb
@@ -5,6 +5,8 @@
 RSpec.describe CopySolvedTopicCustomFieldToDiscourseSolvedSolvedTopics, type: :migration do
   let(:migration) { described_class.new }
 
+  before { enable_current_plugin }
+
   describe "handling duplicates" do
     it "ensures only unique topic_id and answer_post_id are inserted" do
       topic = Fabricate(:topic)
diff --git a/spec/models/directory_item_spec.rb b/spec/models/directory_item_spec.rb
index 7b72585f..98ec3a91 100644
--- a/spec/models/directory_item_spec.rb
+++ b/spec/models/directory_item_spec.rb
@@ -14,7 +14,7 @@
     fab!(:pm) { Fabricate(:topic, archetype: "private_message", user:, category_id: nil) }
     fab!(:pm_post) { Fabricate(:post, topic: pm, user:) }
 
-    before { SiteSetting.solved_enabled = true }
+    before { enable_current_plugin }
 
     it "excludes PM post solutions from solutions" do
       DiscourseSolved.accept_answer!(topic_post1, admin)
diff --git a/spec/models/remove_duplicates_from_discourse_solved_solved_topics_spec.rb b/spec/models/remove_duplicates_from_discourse_solved_solved_topics_spec.rb
index 3df83b6a..0ca8d980 100644
--- a/spec/models/remove_duplicates_from_discourse_solved_solved_topics_spec.rb
+++ b/spec/models/remove_duplicates_from_discourse_solved_solved_topics_spec.rb
@@ -6,6 +6,7 @@
   let(:migration) { described_class.new }
 
   before do
+    enable_current_plugin
     # temp drop unique constraints to allow testing duplicate entries
     ActiveRecord::Base.connection.execute(
       "DROP INDEX IF EXISTS index_discourse_solved_solved_topics_on_topic_id;",
diff --git a/spec/models/site_spec.rb b/spec/models/site_spec.rb
index 5b58c87e..97dfabf7 100644
--- a/spec/models/site_spec.rb
+++ b/spec/models/site_spec.rb
@@ -7,7 +7,10 @@
   let(:category) { Fabricate(:category) }
   let(:guardian) { Guardian.new }
 
-  before { SiteSetting.show_filter_by_solved_status = true }
+  before do
+    enable_current_plugin
+    SiteSetting.show_filter_by_solved_status = true
+  end
 
   it "includes `enable_accepted_answers` custom field for categories" do
     category.custom_fields["enable_accepted_answers"] = true
diff --git a/spec/models/user_summary_spec.rb b/spec/models/user_summary_spec.rb
index 5ba79181..0c5a9272 100644
--- a/spec/models/user_summary_spec.rb
+++ b/spec/models/user_summary_spec.rb
@@ -3,6 +3,8 @@
 describe UserSummary do
   fab!(:admin)
 
+  before { enable_current_plugin }
+
   describe "solved_count" do
     it "indicates the number of times a user's post is a topic's solution" do
       topic = Fabricate(:topic)
diff --git a/spec/requests/answer_controller_spec.rb b/spec/requests/answer_controller_spec.rb
index 4861080f..f039de1e 100644
--- a/spec/requests/answer_controller_spec.rb
+++ b/spec/requests/answer_controller_spec.rb
@@ -11,7 +11,7 @@
   fab!(:solution_post) { Fabricate(:post, topic: topic) }
 
   before do
-    SiteSetting.solved_enabled = true
+    enable_current_plugin
     SiteSetting.allow_solved_on_all_topics = true
     category.custom_fields[DiscourseSolved::ENABLE_ACCEPTED_ANSWERS_CUSTOM_FIELD] = "true"
     category.save_custom_fields
diff --git a/spec/requests/list_controller_spec.rb b/spec/requests/list_controller_spec.rb
index 386c40a2..e0a140bf 100644
--- a/spec/requests/list_controller_spec.rb
+++ b/spec/requests/list_controller_spec.rb
@@ -7,7 +7,10 @@
   fab!(:p2) { Fabricate(:post, topic: p1.topic) }
   fab!(:p3) { Fabricate(:post, topic: p1.topic) }
 
-  before { SiteSetting.allow_solved_on_all_topics = true }
+  before do
+    enable_current_plugin
+    SiteSetting.allow_solved_on_all_topics = true
+  end
 
   it "shows the user who posted the accepted answer second" do
     TopicFeaturedUsers.ensure_consistency!
diff --git a/spec/requests/solved_topics_controller_spec.rb b/spec/requests/solved_topics_controller_spec.rb
index 2cd1ce2d..de334422 100644
--- a/spec/requests/solved_topics_controller_spec.rb
+++ b/spec/requests/solved_topics_controller_spec.rb
@@ -9,6 +9,8 @@
   fab!(:answer_post) { Fabricate(:post, topic:, user:) }
   fab!(:solved_topic) { Fabricate(:solved_topic, topic:, answer_post:) }
 
+  before { enable_current_plugin }
+
   describe "#by_user" do
     context "when accessing with username" do
       it "returns solved posts for the specified user" do
diff --git a/spec/requests/topics_controller_spec.rb b/spec/requests/topics_controller_spec.rb
index e5302df9..24066a46 100644
--- a/spec/requests/topics_controller_spec.rb
+++ b/spec/requests/topics_controller_spec.rb
@@ -7,6 +7,8 @@
   let(:topic) { p1.topic }
   let(:p2) { Fabricate(:post, like_count: 2, topic: topic, user: Fabricate(:user)) }
 
+  before { enable_current_plugin }
+
   def schema_json(answerCount)
     if answerCount > 0
       answer_json =
diff --git a/spec/serializers/topic_answer_mixin_spec.rb b/spec/serializers/topic_answer_mixin_spec.rb
index 489e24a5..1a75e301 100644
--- a/spec/serializers/topic_answer_mixin_spec.rb
+++ b/spec/serializers/topic_answer_mixin_spec.rb
@@ -7,7 +7,10 @@
   let(:post) { Fabricate(:post, topic: topic) }
   let(:guardian) { Guardian.new }
 
-  before { Fabricate(:solved_topic, topic: topic, answer_post: post) }
+  before do
+    enable_current_plugin
+    Fabricate(:solved_topic, topic: topic, answer_post: post)
+  end
 
   it "should have true for `has_accepted_answer` field in each serializer" do
     [
diff --git a/spec/serializers/topic_view_serializer_spec.rb b/spec/serializers/topic_view_serializer_spec.rb
index b3332145..1133d8ca 100644
--- a/spec/serializers/topic_view_serializer_spec.rb
+++ b/spec/serializers/topic_view_serializer_spec.rb
@@ -6,7 +6,7 @@
   fab!(:post2) { Fabricate(:post, topic:) }
   fab!(:user)
 
-  before { SiteSetting.solved_enabled = true }
+  before { enable_current_plugin }
 
   describe "#accepted_answer" do
     it "returns the accepted answer post when the topic has an accepted answer" do
diff --git a/spec/serializers/user_card_serializer_spec.rb b/spec/serializers/user_card_serializer_spec.rb
index 98c38c04..2b3d1b75 100644
--- a/spec/serializers/user_card_serializer_spec.rb
+++ b/spec/serializers/user_card_serializer_spec.rb
@@ -5,6 +5,8 @@
   let(:serializer) { described_class.new(user, scope: Guardian.new, root: false) }
   let(:json) { serializer.as_json }
 
+  before { enable_current_plugin }
+
   it "accepted_answers serializes number of accepted answers" do
     expect(serializer.as_json[:accepted_answers]).to eq(0)
 
diff --git a/spec/system/solved_spec.rb b/spec/system/solved_spec.rb
index c1cf5269..aa99b046 100644
--- a/spec/system/solved_spec.rb
+++ b/spec/system/solved_spec.rb
@@ -9,7 +9,7 @@
   let(:topic_page) { PageObjects::Pages::Topic.new }
 
   before do
-    SiteSetting.solved_enabled = true
+    enable_current_plugin
     SiteSetting.allow_solved_on_all_topics = true
     SiteSetting.accept_all_solutions_allowed_groups = Group::AUTO_GROUPS[:everyone]
     SiteSetting.show_who_marked_solved = true