Fix library

Find the first checks, likely causes, and safe fixes for rooms where Wi-Fi drops or disappears — usually a signal, placement, or interference problem.

Work out why one room is slow while the rest of the home network seems fine — usually a weak path back to the router or a crowded band, not a bad plan.

Diagnose repeated Wi-Fi disconnects across phones, laptops, and smart devices from router load, weak coverage, bad firmware, or IP conflicts.

Get a mesh satellite or node back online without guessing — it is often too far away, on the wrong network, or stuck after a failed setup.

Stabilize a printer, camera, NAS, or smart-home device that keeps getting a new local address — usually a DHCP reservation issue, not a hacked device.

Recover printers, shares, NAS, and smart-home devices after a router changes the home address range, breaking saved paths and manual IP settings.

Separate laptop Wi-Fi, VPN, DNS, browser, and work-management problems when other devices are online and the internet service is not the first suspect.

Check why printers, NAS shares, cameras, or router pages disappear when a VPN connects — it can block local access or route traffic away from home devices.

Diagnose when your ISP put you behind CGNAT (port forwarding broken, WAN IP showing 100.64.x.x), confirm it, then pick a mesh VPN, tunnel, or VPS relay.

Find the path your devices use to bypass Pi-hole — wrong DHCP DNS, an IPv6 leak, browser DoH, hardcoded resolvers — and seal each one.

Web UI 404, custom dnsmasq rules ignored, settings 'lost' — the v5→v6 rewrite changed the web server and config files. Recover cleanly.

After putting devices on a separate VLAN, Chromecast/AirPlay/AirPrint vanish. It's mDNS not crossing the VLAN — reflect discovery and allow the media path.

Forwarded a port and still can't reach the service? Work the real causes in order — CGNAT, double-NAT, the hairpin test trap, ISP-blocked 80/443, wrong IP.

When Pi-hole is the only DNS you hand out and it dies, the whole house loses name resolution. Restore service fast, then build real redundancy.

Some sites hang or load slowly, or a VPN leaks? Find whether IPv6 is the cause, fix the real fault, and know when disabling it is just a band-aid.

MoCA adapters won't link over your coax? Work the real causes: a missing point-of-entry filter, an old splitter blocking MoCA frequencies, or no clean path.

Your 2.5GbE NIC or switch only links at 1GbE? It's rarely the cable — check auto-negotiation, Energy-Efficient Ethernet, the driver, and the port.

Fix buffering on one TV when the internet is fast — the per-stream bandwidth that matters (4K is about 15 Mbps), the 2.4GHz/distance trap, and the wired test.

Fix an Apple TV / Fire TV / Chromecast / Roku that won't join or keeps dropping Wi-Fi — band mismatch, captive portals, the IoT-VLAN/mDNS trap, and resets.

Find the safe first checks when a monitor through a USB-C dock stays blank — cable, port capability, dock power, display input, or OS settings.

Check power delivery basics before replacing a dock, laptop charger, or cable when a dock runs peripherals but fails to charge the host laptop.

Plan the first safe checks when a dock or laptop drives only one external display — usually bandwidth, port limits, cable limits, or OS arrangement.

Fix a monitor stuck at the wrong refresh rate without unsafe cable or adapter guesses — the whole chain from monitor to graphics settings limits it.

Tell whether a USB-C cable is the wrong type for charging, display, data, or docking — the connector shape does not promise every capability.

Check cable, refresh rate, dock power, and bandwidth limits when a docked monitor flickers — often the display path is barely stable, not a broken monitor.

Check clamshell mode, power settings, charger state, and dock behavior when closing a laptop turns off the monitor — usually a setting, not a failed monitor.

Your dock's SSD slows when a monitor's plugged in, or it won't hit rated speed? Learn the shared 'bandwidth budget' and find what's eating it.

Fix an HDMI 'No Signal' / black screen: rule out wrong input, isolate cable vs port, and force a clean HPD/EDID handshake in the right power-cycle order.

Get HDMI-CEC one-remote control and auto-switch working — enable it on every device under its trade name (Anynet+, BRAVIA Sync, SimpLink) and fix the AVR.

Fix soundbar/AVR audio over HDMI — use the eARC/ARC port, keep CEC on, set the TV to bitstream/passthrough, and know why eARC is needed for Dolby Atmos.

Fix content-protected / black-or-pink-screen HDCP errors on 4K HDR — the weakest-link rule (every device needs HDCP 2.2+), the AVR/splitter trap, and reset.

Fix a TV input stuck at 1080p/4K30 or refusing HDR — enable the per-input Enhanced/Deep Color setting, use an Ultra High Speed cable, and check HDMI 2.1.

Fix 4K120 / VRR / ALLM on a PS5 or Xbox through a TV or AVR — the optional-HDMI-2.1 reality, the AVR-passthrough trap, per-input toggles, and the right cable.

Reset the pairing path for headphones, keyboards, speakers, and controllers without wiping everything — the device is often still paired elsewhere.

Get a smart plug onto the right Wi-Fi network without weakening the home setup — usually 2.4 GHz needs, app account state, distance, or stale factory setup.

Recover a missing network printer without reinstalling everything first — it is usually offline, on the wrong Wi-Fi, at a changed IP, or behind a stale queue.

Work through camera permissions, cables, apps, and drivers before replacing a webcam that is missing, held by another app, or blocked by privacy settings.

Bring smart plugs, bulbs, cameras, and hubs back carefully after a power cut without resetting the whole home, even when they reconnect slowly or miss Wi-Fi.

Check printer status, IP address, queue state, and network path first — a printer can be on Wi-Fi yet appear offline from an old address or stuck queue.

Diagnose Matter-over-Thread pairing failures: border router presence, network credentials, IPv6 reachability, 2.4 GHz channel collision, and the fabric model.

Recover when the Zigbee coordinator (Hue Bridge, SmartThings, ConBee, Sonoff, ZHA, Zigbee2MQTT) goes offline: backup-restore, network healing, and re-pairing.

Troubleshoot a Windows file share in order: path, host, network profile, discovery, credentials, permissions, firewall, and SMB safety.

Triage failed home backups before deleting jobs, drives, or old versions — the device slept, the destination vanished, the disk filled, or login changed.

Check cable, power, ports, disk health, and backup safety before reformatting a missing drive — it can be a loose cable or early disk failure.

Find a home NAS on the network when it disappears — usually offline, on a changed IP, blocked by discovery, or waiting on storage and network health checks.

Check account, bandwidth, excluded files, sleep settings, and local backup coverage before trusting a stalled cloud backup.

Free backup space safely using retention settings, not random deletion inside the backup folder, which can damage the indexes or chains your set depends on.

Separate direct play, transcoding, network, and storage causes when a NAS-hosted Plex stream buffers — read the server dashboard, then the layer it points at.

Diagnose Plex remote access failures by reading the server Remote Access status — CGNAT, double-NAT, UPnP versus manual port mapping, and Plex Relay fallback.

Diagnose the Synology Unverified drive warning after the October 2025 reversal: what is still blocked vs warning-only by model, and how to acknowledge it.

Pre-upgrade runbook and post-upgrade fixes for TrueNAS Scale 24.10 to 25.04 (Fangtooth) and 25.10 (Goldeye): VM migration, IOMMU regression, BE rollback.

A calm, ordered ransomware-recovery runbook for a home NAS or server — isolate before you restore, check whether backups are clean, recover, and report.

Estimate why a UPS does not last as long as expected and decide what to unplug first — runtime depends on watt load, battery age, health, and outlet use.

Check load, battery health, outlet power, and alarm meaning when a UPS keeps beeping after power returns — on battery, overloaded, or reporting a bad battery.

Check power adapter, heat, outlet, UPS, and device load when a router restarts itself — it may be a power, heat, firmware, or hardware fault, not coverage.