Give more detail about why the import failed

app/mailers/import_mailer.rb

@@ -4,7 +4,8 @@ class ImportMailer < ApplicationMailer
     mail to: identity.email_address, subject: "Your Fizzy account import is done"
   end
 
-  def failed(identity)
-    mail to: identity.email_address, subject: "Your Fizzy account import failed"
+  def failed(import)
+    @import = import
+    mail to: import.identity.email_address, subject: "Your Fizzy account import failed"
   end
 end

app/models/account/data_transfer/record_set.rb

@@ -1,5 +1,6 @@
 class Account::DataTransfer::RecordSet
   class IntegrityError < StandardError; end
+  class ConflictError < IntegrityError; end
 
   IMPORT_BATCH_SIZE = 100
 
@@ -93,7 +94,7 @@ class Account::DataTransfer::RecordSet
       end
 
       if model.exists?(id: data["id"])
-        raise IntegrityError, "#{model} record with ID #{data['id']} already exists"
+        raise ConflictError, "#{model} record with ID #{data['id']} already exists"
       end
 
       check_associations_dont_exist(data)
@@ -118,7 +119,7 @@ class Account::DataTransfer::RecordSet
       end
 
       if associated_class.exists?(id: associated_id)
-        raise IntegrityError, "#{model} record references existing #{association.name} (#{associated_class}) with ID #{associated_id}"
+        raise ConflictError, "#{model} record references existing #{association.name} (#{associated_class}) with ID #{associated_id}"
       end
     end
 

app/models/account/import.rb

@@ -7,6 +7,7 @@ class Account::Import < ApplicationRecord
   has_one_attached :file
 
   enum :status, %w[ pending processing completed failed ].index_by(&:itself), default: :pending
+  enum :failure_reason, %w[ conflict invalid_export ].index_by(&:itself), prefix: :failed_due_to, scopes: false
 
   scope :expired, -> { where(completed_at: ...24.hours.ago).or(where(status: :failed, created_at: ...7.days.ago)) }
 
@@ -26,6 +27,12 @@ class Account::Import < ApplicationRecord
         record_set.check(from: zip, start: last_id, callback: callback)
       end
     end
+  rescue Account::DataTransfer::RecordSet::ConflictError => e
+    mark_as_failed(:conflict)
+    raise e
+  rescue Account::DataTransfer::RecordSet::IntegrityError, ZipFile::InvalidFileError => e
+    mark_as_failed(:invalid_export)
+    raise e
   rescue => e
     mark_as_failed
     raise e
@@ -44,6 +51,12 @@ class Account::Import < ApplicationRecord
     reconcile_account_storage
 
     mark_completed
+  rescue Account::DataTransfer::RecordSet::ConflictError => e
+    mark_as_failed(:conflict)
+    raise e
+  rescue Account::DataTransfer::RecordSet::IntegrityError, ZipFile::InvalidFileError => e
+    mark_as_failed(:invalid_export)
+    raise e
   rescue => e
     mark_as_failed
     raise e
@@ -60,9 +73,9 @@ class Account::Import < ApplicationRecord
       ImportMailer.completed(identity, account).deliver_later
     end
 
-    def mark_as_failed
-      failed!
-      ImportMailer.failed(identity).deliver_later
+    def mark_as_failed(failure_reason = nil)
+      update!(status: :failed, failure_reason: failure_reason)
+      ImportMailer.failed(self).deliver_later
     end
 
     def add_importer_to_all_access_boards

app/views/account/imports/show.html.erb

@@ -13,7 +13,13 @@
     <%= link_to "Go to your account", landing_url(script_name: @import.account.slug), class: "btn btn--link center txt-medium" %>
   <% when "failed" %>
     <p class="txt-medium txt-negative">Your import failed.</p>
-    <p class="txt-small">This may be due to corrupted export data or a conflict with existing data. Please try again with a fresh export.</p>
+    <% if @import.failed_due_to_conflict? %>
+      <p class="txt-small">It looks like the account you are trying to import already exists.</p>
+    <% elsif @import.failed_due_to_invalid_export? %>
+      <p class="txt-small">The ZIP file isn't a Fizzy account export.</p>
+    <% else %>
+      <p class="txt-small">This may be due to corrupted export data or a conflict with existing data. Please try again with a fresh export.</p>
+    <% end %>
     <%= link_to "Try again", new_account_import_path, class: "btn btn--plain center txt-medium" %>
   <% end %>
 </div>

app/views/mailers/import_mailer/failed.html.erb

@@ -1,8 +1,11 @@
 <p class="subtitle">Unfortunately, we couldn't import your Fizzy account.</p>
 
-<p>
-This may be due to corrupted export data or a conflict with existing data.
-Please try again with a fresh export, or reach out for help if the problem persists.
-</p>
+<% if @import.failed_due_to_conflict? %>
+  <p>It looks like the account you are trying to import already exists.</p>
+<% elsif @import.failed_due_to_invalid_export? %>
+  <p>The ZIP file isn't a Fizzy account export.</p>
+<% else %>
+  <p>This may be due to corrupted export data or a conflict with existing data. Please try again with a fresh export, or reach out for help if the problem persists.</p>
+<% end %>
 
 <p class="footer">Need help? <%= mail_to "support@fizzy.do", "Send us an email" %>.</p>

app/views/mailers/import_mailer/failed.text.erb

@@ -1,6 +1,11 @@
 Unfortunately, we couldn't import your Fizzy account.
 
-This may be due to corrupted export data or a conflict with existing data.
-Please try again with a fresh export, or reach out for help if the problem persists.
+<% if @import.failed_due_to_conflict? -%>
+It looks like the account you are trying to import already exists.
+<% elsif @import.failed_due_to_invalid_export? -%>
+The ZIP file isn't a Fizzy account export.
+<% else -%>
+This may be due to corrupted export data or a conflict with existing data. Please try again with a fresh export, or reach out for help if the problem persists.
+<% end -%>
 
 Need help? Send us an email at support@fizzy.do

db/migrate/20260211122517_add_failure_reason_to_account_imports.rb

@@ -0,0 +1,5 @@
+class AddFailureReasonToAccountImports < ActiveRecord::Migration[8.2]
+  def change
+    add_column :account_imports, :failure_reason, :string
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.2].define(version: 2026_01_21_155752) do
+ActiveRecord::Schema[8.2].define(version: 2026_02_11_122517) do
   create_table "accesses", id: :uuid, charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.datetime "accessed_at"
     t.uuid "account_id", null: false
@@ -42,6 +42,7 @@ ActiveRecord::Schema[8.2].define(version: 2026_01_21_155752) do
     t.uuid "account_id"
     t.datetime "completed_at"
     t.datetime "created_at", null: false
+    t.string "failure_reason"
     t.uuid "identity_id", null: false
     t.string "status", default: "pending", null: false
     t.datetime "updated_at", null: false

db/schema_sqlite.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.2].define(version: 2026_01_21_155752) do
+ActiveRecord::Schema[8.2].define(version: 2026_02_11_122517) do
   create_table "accesses", id: :uuid, force: :cascade do |t|
     t.datetime "accessed_at"
     t.uuid "account_id", null: false
@@ -42,6 +42,7 @@ ActiveRecord::Schema[8.2].define(version: 2026_01_21_155752) do
     t.uuid "account_id"
     t.datetime "completed_at"
     t.datetime "created_at", null: false
+    t.string "failure_reason"
     t.uuid "identity_id", null: false
     t.string "status", limit: 255, default: "pending", null: false
     t.datetime "updated_at", null: false

test/mailers/import_mailer_test.rb

@@ -12,4 +12,39 @@ class ImportMailerTest < ActionMailer::TestCase
     assert_equal "Your Fizzy account import is done", email.subject
     assert_match accounts(:"37s").slug, email.body.encoded
   end
+
+  test "failed with no reason" do
+    import = Account::Import.create!(account: Current.account, identity: identities(:david), status: :failed)
+    email = ImportMailer.failed(import)
+
+    assert_emails 1 do
+      email.deliver_now
+    end
+
+    assert_equal [ "david@37signals.com" ], email.to
+    assert_equal "Your Fizzy account import failed", email.subject
+    assert_match "corrupted export data", email.body.encoded
+  end
+
+  test "failed with conflict reason" do
+    import = Account::Import.create!(account: Current.account, identity: identities(:david), status: :failed, failure_reason: :conflict)
+    email = ImportMailer.failed(import)
+
+    assert_emails 1 do
+      email.deliver_now
+    end
+
+    assert_match "account you are trying to import already exists", email.body.encoded
+  end
+
+  test "failed with invalid_export reason" do
+    import = Account::Import.create!(account: Current.account, identity: identities(:david), status: :failed, failure_reason: :invalid_export)
+    email = ImportMailer.failed(import)
+
+    assert_emails 1 do
+      email.deliver_now
+    end
+
+    assert_match "isn't a Fizzy account export", email.body.encoded
+  end
 end

test/models/account/import_test.rb

@@ -62,6 +62,67 @@ class Account::ImportTest < ActiveSupport::TestCase
     export_tempfile&.unlink
   end
 
+  test "check sets no failure_reason for unexpected errors" do
+    import = Account::Import.create!(identity: identities(:david), account: Account.create!(name: "Import Test"))
+
+    assert_raises(NoMethodError) { import.check }
+
+    assert import.failed?
+    assert_nil import.failure_reason
+  end
+
+  test "check sets failure_reason to invalid_export for non-Fizzy ZIP" do
+    target_account = Account.create!(name: "Import Test")
+    import = Account::Import.create!(identity: identities(:david), account: target_account)
+
+    # Create a ZIP with no account.json
+    tempfile = Tempfile.new([ "bad_export", ".zip" ])
+    tempfile.binmode
+    writer = ZipFile::Writer.new(tempfile)
+    writer.add_file("data/dummy.json", '{"hello": "world"}')
+    writer.close
+    tempfile.rewind
+
+    Current.set(account: target_account) do
+      import.file.attach(io: tempfile, filename: "export.zip", content_type: "application/zip")
+    end
+
+    assert_raises(Account::DataTransfer::RecordSet::IntegrityError) { import.check }
+
+    assert import.failed?
+    assert_equal "invalid_export", import.failure_reason
+  ensure
+    tempfile&.close
+    tempfile&.unlink
+  end
+
+  test "check sets failure_reason to conflict when records already exist" do
+    source_account = accounts("37s")
+    exporter = users(:david)
+    identity = exporter.identity
+
+    export = Account::Export.create!(account: source_account, user: exporter)
+    export.build
+
+    export_tempfile = Tempfile.new([ "export", ".zip" ])
+    export.file.open { |f| FileUtils.cp(f.path, export_tempfile.path) }
+
+    # Import without destroying the source, so records still exist
+    target_account = Account.create_with_owner(account: { name: "Import Test" }, owner: { identity: identity, name: exporter.name })
+    import = Account::Import.create!(identity: identity, account: target_account)
+    Current.set(account: target_account) do
+      import.file.attach(io: File.open(export_tempfile.path), filename: "export.zip", content_type: "application/zip")
+    end
+
+    assert_raises(Account::DataTransfer::RecordSet::ConflictError) { import.check }
+
+    assert import.failed?
+    assert_equal "conflict", import.failure_reason
+  ensure
+    export_tempfile&.close
+    export_tempfile&.unlink
+  end
+
   private
     def account_digest(account)
       {