Windows 7: Sleeping computers invisible on LAN; Need WOL

MS says that Wake-on-Lan is on by default in Win 7. I've upgraded 5 of my machines to Win 7 and none of them are visible on the LAN when in sleep mode. They are all visible when awake. Is there a magic packet we need to load to wake them up? Anyone have this problem also?

Hello,

To wake on LAN, you do need to send a magic packet. Many sites and utilities facilitate this. Here's is the one I use: Depicus

Let me know if you need help with that program.

your hardware has to support such a feature. Often you need to turn it on in the bios if you have an on board nic.

You will not see the machines on the network while they are sleeping. And as Jonathan pointed out, you have to have a utility to send the magic packet to wake the machine.

In your user folder, make a folder "Network" and in that folder make shortcuts to the machines on your LAN ... Probing them from the shortcut should wake them up.. or at least it does on mine.

The "magic packet" is simply a "Ping" sent to any port on the machine.

Also, be aware that "Wake On LAN" doesn't work with wireless devices as they turn off their radios when going standby.

This may clear up some comfusion: Wake-on-LAN - Wikipedia, the free encyclopedia

A magic packet is a series of 16 F's. If enabled, the network card reserves just enough power to listen for that signal.

Regardless... the shortcuts trick does work.

Hey Jonathan, Naxcid, and CommonTater, thanks a lot for very helpful advice and info.

I looked at the Depicus program and read the Wiki article. I've adjusted the power-on settings in the bios of my machines and I've made sure that all of the network adapters will use the magic packet to wake up.

However, I'm not the brightest bulb in the networking department. So I take it that I must get the MAC address of each machine I want to wake and then make those shortcuts (?) you suggested with the appropriate address in each one. I'm not sure how that would look or be done (?).

Am I on the right track here? First step to get the MAC addresses of each machine?

Thanks for the great suggestions and advice! I've been bothered by this for years.

You need the mac addresses of the network cards. Open up a command prompt and enter ipconfig /all.

You'll find the mac address here.

It doesn't need to be complicated. In your user folder right click and select New then Folder... name it "Network" or whatever suits... Now open my network with all your machines running (so you can see them) and drag the icons over to the new folder. Now when you click on them in the new folder they will cause the system to probe the machine and wake it up. Knowing Windows 7 you may have to click the icon 3 or 4 times, cancelling suggestions that the machine is not available before it actually gives you a list of shares....

(On XP this trick was the best replacement you could have for "My Network Places" and would give you a list of shares right off the bat... Win 7 is a bit slow on the uptake but it does eventually get the idea.)

No he doesn't... in his adaptor properties he only needs to enable "Wake in Magic Packet" and "Wake on Pattern". In the shortcut itself he only needs the computer's name in UNC format... For example if the machine is named "fred" the target slot in the shortcut would read \\fred ... its the same as making a shortcut to a folder ... all you need is the folder's name. A network address is seen as a system folder, just like any other.

Heres the thing... Network adaptors have no brains, they rely upon the CPU to make their decisions for them. ANYTHING coming into a network port requires the machine to wakeup, examine the packet and decide what to do with it... Some software might decide not to allow connecting to the port, or others might implement a secure ACK-NAK sequence... but it has to wake the machine out of standby to do that.

So... no matter what you send to that port it's going to wake the machine up. From there it will discard the bad first packet, but it's awake now so it will process the request for a share list from the shortcut.

Yes it's an exploit... the bane of modern computing... but hey if it works....