diff --git a/config/initializers/core_extensions.rb b/config/initializers/core_extensions.rb
index 2e9ed7e1..d6039e16 100644
--- a/config/initializers/core_extensions.rb
+++ b/config/initializers/core_extensions.rb
@@ -93,8 +93,8 @@ module Jekyll
 
         unless spec
           I18n.with_locale(locale) do
-            raise ArgumentError, I18n.t('activerecord.errors.models.site.attributes.design_id.missing_gem', theme: name)
-          rescue ArgumentError => e
+            raise Jekyll::Errors::InvalidThemeName, I18n.t('activerecord.errors.models.site.attributes.design_id.missing_gem', theme: name)
+          rescue Jekyll::Errors::InvalidThemeName => e
             ExceptionNotifier.notify_exception(e, data: { theme: name, site: File.basename(site.source) })
             raise
           end