diff --git a/source/_integrations/smtp.markdown b/source/_integrations/smtp.markdown
index a730d1f56c6..3902e8785dc 100644
--- a/source/_integrations/smtp.markdown
+++ b/source/_integrations/smtp.markdown
@@ -113,6 +113,12 @@ The optional `html` field makes a custom text/HTML multi-part message, allowing
 
 The optional `images` field adds image attachments to the email. If `html` is defined, the images need to be added to the message in-line as described above (and as shown in the example below). If `html` is not defined, images will be added as separate attachments.
 
+<div class='note info'>
+
+When adding images, make sure the folders containing the attachments are added to `allowlist_external_dirs`.<br>See: [Setup basic documentation](/docs/configuration/basic/)
+
+</div>
+
 ```yaml
 burglar:
   alias: "Burglar Alarm"