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Remove ‘Untrusted Certificate’ Errors in Apple Mail, Outlook, and Thunderbird for iRedMail

Remove ‘Untrusted Certificate’ Errors in Apple Mail, Outlook, and Thunderbird for iRedMail

May 22, 2026 | Advanced Linux Scripting, Learn Linux in practical way

Tired of “untrusted certificate” warnings in your email client? Replace iRedMail’s self-signed SSL certificates with free Let’s Encrypt certificates. Step-by-step guide for Rocky Linux, Ubuntu, and more. You’ve just set up iRedMail and...
Postfix SASL Authentication Failed: Fixing ‘No SASL authentication mechanisms’ in iRedMail

Postfix SASL Authentication Failed: Fixing ‘No SASL authentication mechanisms’ in iRedMail

May 22, 2026 | Advanced Linux Scripting, Learn Linux in practical way

You’ve just set up iRedMail, configured your domains, and created email accounts. Everything seems perfect until you try to send an email from your desktop client. Instead of a sent confirmation, you’re staring at an error message in your mail logs:...
How to Set Up Let’s Encrypt SSL for iRedMail on Rocky Linux 10.1, RHEL, CentOS, Fedora, and Ubuntu

How to Set Up Let’s Encrypt SSL for iRedMail on Rocky Linux 10.1, RHEL, CentOS, Fedora, and Ubuntu

May 22, 2026 | Advanced Linux Scripting, Learn Linux in practical way

Introduction iRedMail is a powerful open-source mail server solution that comes with self-signed SSL certificates by default. While self-signed certificates work, they trigger security warnings in email clients like Apple Mail, Outlook, and Thunderbird. This tutorial...
nmcli Complete Command Guide

nmcli Complete Command Guide

Apr 21, 2026 | Advanced Linux Scripting, Learn Linux in practical way

Essential Examples for System Administrators (Bridge, VLAN, and SSH Safety) NetworkManager’s command-line tool nmcli is a powerful utility for managing network connections on Linux servers. For system administrators, mastering nmcli is essential—it allows you to...
How to Manage Plesk Firewall from the Command Line: A Complete Guide

How to Manage Plesk Firewall from the Command Line: A Complete Guide

Apr 8, 2026 | Learn Linux in practical way

Introduction Managing firewall rules through Plesk’s web interface is straightforward, but there are times when you only have SSH access to your server. Whether you’re troubleshooting a lockdown situation, automating server configuration, or simply prefer...
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