Fix “opendkim-testkey: unexpected reply class/type (-1/-1)”
OpenDKIM can’t look up your DKIM record. Give it working DNS resolvers with the Nameservers setting, restart and test again.
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Guides & Tips
Practical, tested guides on Windows, Linux, networking, email servers and WordPress – written from real support work.
Free Up Disk Space on Ubuntu: Clean Unused Packages with apt autoremove
Remove dependencies and old kernels you no longer need, clear the package cache and see how much space you got back.
Elementor “Can’t Edit?” Error on Nginx: Fix the try_files Rule
If Elementor shows “Having trouble loading Elementor? Please enable Safe Mode”, your Nginx config may be dropping query strings. One word fixes…
After Upgrading Ubuntu 20.04 to 22.04: Fix Nginx and PHP-FPM (PHP 7.4 → 8.1)
Sites down after a do-release-upgrade? Ubuntu 22.04 ships PHP 8.1, so Nginx is still pointing at a php7.4-fpm socket that no longer…
Disable Right-Click on a WordPress Site (and What It Can’t Protect)
Add a few lines to a child theme or a small plugin to block the context menu across your WordPress site –…
Set a Static IP on Ubuntu with a Bash Script (Netplan, 18.04–24.04)
An interactive script that detects your interface and Ubuntu release, writes the correct Netplan file and applies it safely with netplan try.
Taskkill: Stop Windows Processes from the Command Line
End frozen apps and stubborn processes by name, PID or filter – locally or on a remote PC – with the built-in…
One-Command Ubuntu Updates: A Safe Update Script
Update package lists, show what will change, upgrade and clean up in one command – with error checks and a reboot reminder.
Extend an LVM Logical Volume on Ubuntu Server (Use All Your Disk)
Ubuntu’s installer often uses only part of the disk for the root volume. Check free space with vgdisplay, extend with lvextend and…