Merge pull request #6605 from bszyman/main

Author: sofietoft

14/umbraco-cms/tutorials/custom-error-page.md

@@ -37,17 +37,18 @@ This method will use a 404 page created via the backoffice.
 1. Navigate to the **Settings** section.
 2. Create a new "_Document Type with Template_".
 3. Name the Document Type **404**.
-4. \[Optional] Add properties on the Document Type.
+4. Adjust the alias to "Page404" before saving the Document Type. Umbraco will not allow you to create a Document Type with a numeric alias.
+5. \[Optional] Add properties on the Document Type.
    1. In most cases, the 404 not found page would be static.
-5. Fill out the Template with your custom markup.
-6. Create another **Document Type**, but create it without the Template.
-7. Call this Document Type **Statuscodes**.
-8. Open the **Structure** Workspace view.
-9. Check the **Allow at root** option.
-10. Add the **404** Document Type as an **Allowed child note type**.
-11. Navigate to the **Content** section.
-12. Create a **Statuscodes** content item called **Statuscodes**.
-13. Create a **404** content item under the **Statuscodes** content.
+6. Fill out the Template with your custom markup.
+7. Create another **Document Type**, but create it without the Template.
+8. Call this Document Type **Statuscodes**.
+9. Open the **Structure** Workspace view.
+10. Check the **Allow at root** option.
+11. Add the **404 Page** Document Type as an **Allowed child note type**.
+12. Navigate to the **Content** section.
+13. Create a **Statuscodes** content item called **Statuscodes**.
+14. Create a **404 Page** content item under the **Statuscodes** content.
 
 ### Set a custom 404 page in the configuration