diff --git a/docs/debug-common_problems.md b/docs/debug-common_problems.md
index 095f428c8..fdcb937bb 100644
--- a/docs/debug-common_problems.md
+++ b/docs/debug-common_problems.md
@@ -56,6 +56,7 @@ while trying to start / install mailcow: dockerized, make sure you've followed o
 ## XYZ can't connect to ...
 
 Please check your local firewall!
+Docker and iptables-based firewalls sometimes create conflicting rules, so disable the firewall on your host to determine whether your connection issues are caused by such conflicts. If they are, you need to manually create appropriate rules in your host firewall to permit the necessary connections.
 
 If you experience connection problems from home, please check your ISP router's firewall too, some of them block mail traffic on the *SMTP* (587) or *SMTPS* (465) ports. It could also be, that your ISP is blocking the ports for *SUBMISSION* (25).
 
diff --git a/docs/u_e-dovecot-expunge.md b/docs/u_e-dovecot-expunge.md
index 19cd21a14..52d0062cd 100644
--- a/docs/u_e-dovecot-expunge.md
+++ b/docs/u_e-dovecot-expunge.md
@@ -31,8 +31,8 @@ If you want to automate such a task you can create a cron job on your host that
 
 ```
 #!/bin/bash
-/usr/local/bin/docker-compose exec -T doveadm dovecot-mailcow doveadm expunge -A mailbox 'Junk' savedbefore 2w
-/usr/local/bin/docker-compose exec -T doveadm expunge -A mailbox 'Junk' SEEN not SINCE 12h
+/usr/local/bin/docker-compose exec dovecot-mailcow doveadm expunge -A mailbox 'Junk' savedbefore 2w
+/usr/local/bin/docker-compose exec dovecot-mailcow doveadm expunge -A mailbox 'Junk' SEEN not SINCE 12h
 [...]
 ```