Why does Wake-on-LAN work from sleep but not from shutdown?

Windows Fast Startup. It turns Shut Down into a hybrid hibernate that leaves the network card unarmed, while Sleep leaves it listening. Disabling Fast Startup fixes this and is the single most common cause.

How can I tell if the network card still has power after shutdown?

Look at the link light on the network port, or check whether the switch still shows the port as up. If the light dies at the same moment the PC does, the card has no standby power and no magic packet can ever reach it.

Can Wake-on-LAN work over the internet?

Not reliably, and you should not try. A magic packet is a LAN broadcast. The practical approach is to have a machine already inside the venue send it, so nothing needs to be exposed to the internet.

Wake-on-LAN not working on a simulator PC? The 5 real causes

You send the packet. The rig stays dark. Here is what is actually going on, in the order it is usually going on, and how to tell which one you have.

Written from running three simulator venues · Updated August 2026

Wake-on-LAN has one requirement that everything else follows from: the network card has to stay powered after the PC shuts down, listening for a magic packet. If it is not listening, nothing you send matters. Every cause below is a different way that requirement gets broken.

First: is the card even awake?

Do this before changing a single setting. Shut the PC down normally, then look at the network port.

Link light still on — the card has standby power and is probably listening. Your problem is further down this page.
Link light goes dark with the PC — the card lost power. Nothing can wake it. Causes 1, 4 and 5 below.

From our own venue, 2026-08-08

A rig called Russell would not wake. Three magic packets, all sent to the correct MAC address, all confirmed leaving another machine on the same network. The fault was visible on the wire: its network card went dark the same minute the PC did. The packets were perfect and completely irrelevant. Two minutes with the link light would have saved an evening of debugging.

1. Windows Fast Startup (the usual culprit)

This is the cause most of the time, and it is the most confusing one, because the machine wakes fine from Sleep and never from Shut Down.

Fast Startup makes "Shut down" into a hybrid hibernate. The PC looks off, but it took a shortcut on the way there, and one thing skipped is arming the network card. Sleep does not take that shortcut, which is why Sleep works and Shut Down does not.

Turn it off:

Control Panel → Power Options → Choose what the power buttons do
→ Change settings that are currently unavailable
→ untick "Turn on fast startup"

Or from an admin prompt:

powercfg /hibernate off

2. Wake-on-LAN disabled in the BIOS

Named differently by nearly every manufacturer. Look for Wake on LAN, Power On by PCI-E, Resume by PCI-E Device, or Power On by Onboard LAN, usually under Power Management.

This one needs somebody physically at the machine, which is exactly the problem you were trying to solve. While you are standing there, see the list at the bottom — there are three other settings worth changing in the same visit.

3. The network driver is not allowed to wake the PC

Device Manager → your network adapter → Properties:

Power Management tab: tick Allow this device to wake the computer. Untick Allow the computer to turn off this device to save power.
Advanced tab: Wake on Magic Packet → Enabled.
Also on Advanced: turn off Wake on pattern match. Leaving it on means stray network traffic wakes your rigs at 3am, and a row of simulators that switches itself on overnight is its own kind of problem.
Realtek cards: turn off Green Ethernet and Energy Efficient Ethernet. Both can cut the card's power in standby.

4. BIOS deep sleep / ErP mode

ErP (sometimes "Deep Sleep Control" or "EuP 2013") is a power-saving standard that cuts standby power to the PCIe bus entirely when the machine is off. It is a compliance feature and it does its job well, which here means killing your network card stone dead. Disable ErP.

This is a common cause of the link-light-goes-dark symptom, and it is easy to miss because it sounds unrelated to networking.

5. The power is actually off

Worth saying plainly: if the wall switch, power strip, or PSU switch is off, no BIOS setting on earth will help. In a venue this is more likely than it sounds — cleaners switch strips off, and a rig on a timer strip is dead to the world between timings.

If this is a recurring problem, the fix is not Wake-on-LAN at all. See the alternatives below.

While you are at the machine anyway

The expensive part of all this is the drive to the venue. If you are standing at a rig with the BIOS open, change all of these in the one visit:

Setting	Set to	Why
Wake on LAN / Power On by PCI-E	Enabled	The thing you came for
ErP / Deep Sleep	Disabled	Otherwise the card has no standby power
Restore on AC Power Loss	Power On	The rig comes back by itself after an outage, and makes a smart plug a working power switch
Power On by RTC Alarm	Enabled, set to opening time	The whole row powers itself up every morning with no network involved at all

The RTC alarm is underrated

It costs nothing, involves no network, and cannot be broken by an internet outage. Pair it with a scheduled nightly shutdown and your rigs power themselves down at close and back up before opening, permanently, with no software involved. Do this even if Wake-on-LAN works.

When Wake-on-LAN is the wrong tool

Wake-on-LAN cannot recover a machine whose power is physically cut, and it cannot get you into a BIOS. If either is your real problem, these do work:

Option	Cost	What it solves
BIOS RTC alarm	Free	Scheduled power-on. No network. Do this regardless.
Smart plug with a local API (e.g. Shelly Plug US Gen4)	~$20	True remote power cycling. Wattage reporting also tells you "4W, genuinely off" from "180W, powered but the PC is hung" — a distinction that decides whether you need to drive over.
IP KVM with an ATX board (JetKVM, NanoKVM)	$70–$105	BIOS-level remote screen plus power on/off/reset. Ends the "someone has to visit to change a BIOS setting" problem for good.

Two warnings from experience

Cloud-only smart plugs are the wrong tool. If the venue's internet is down, so is the plug — and the venue's internet being down is exactly when you need it. Insist on a local HTTP API. We pulled a set of cloud-only plugs out of our venues for this reason.

vPro and IPMI are not options here. They need business or server motherboards. Simulator rigs are consumer gaming PCs, and they do not have it.

Do not expose Wake-on-LAN to the internet

A magic packet is a LAN broadcast. Forwarding a port so you can send one from outside means opening a hole in the venue's firewall for a protocol with no authentication whatsoever.

The right shape is to have a machine already inside the venue send the packet on your behalf. Any always-on PC on that network can do it — nothing needs to be exposed, and no firewall rule is required.

This is what SimCenter does

SimCenter runs a small agent on each simulator PC. Any station that is awake can wake a sleeping one on the same network, so you power a bay on from your phone without opening a single port. It also arms the Windows side of Wake-on-LAN across a whole venue in one click — Fast Startup, magic packet, the pattern-wake and Green Ethernet settings above — and tells you honestly which machines still need a BIOS visit.

And when a rig is genuinely unreachable, it says so before a customer walks into the bay and finds out for you.

See how SimCenter works →