diff --git a/FAQ-and-Tips.md b/FAQ-and-Tips.md
index 3b3b1a8..1c0b472 100644
--- a/FAQ-and-Tips.md
+++ b/FAQ-and-Tips.md
@@ -232,6 +232,13 @@ mail amavis[1459]: (01459-01) (!)ClamAV-clamscan av-scanner FAILED: /usr/bin/cla
 mail amavis[1459]: (01459-01) (!!)AV: ALL VIRUS SCANNERS FAILED
 # Clamav is not running (not started or because you don't have enough memory)
 # => check requirements and/or start Clamav
+```
+### Using behind proxy
+Add to `/etc/postfix/main.cf` :
+```
+ 
+proxy_interfaces = X.X.X.X (your public IP) 
+
 ```
 
 ### What about updates