[Tril]

I've got an Asus P5E3 Deluxe WiFi-AP @n Motherboard in my pc. I've got a home network with a few computers connected to a switch. The switch is connected to a router connected to the internet. The pc are all wired. My pc has two ethernet connectors. I use one of them. I haven't tried the other lately.

I usually leave my computer on 24/7 because I've got a tv tuner and it records tv shows. Lately, I shut down my computer two times two different days.

The first time I powered off, I noticed that the internet was down on the other computers. I also tried to connect to the router with its ip in a browser and it did not work. I rebooted the computer and internet came back in the other pcs.

The other time I powered it off, internet stopped working on the other pc again. I disconnected the ethernet cable from my computer and the internet connection came back on the other pcs. When the pc is on, that ethernet port works and internet works fine.

I've tried to search for other people experiencing this on the net but so far I've found nothing. I'm wondering if this is happenning because of a bad setting in the bios related to the wake on lan setting or something like that. Or, if there's something defective with the motherboard.

It might also be a problem with the ethernet switch.

[Takaharu]

Does your PC have a static or dynamic IP address? I.e.: did you set the IP of your network connection or does the router set it for you?
If your PC is acting as a DHCP server in addition to the router then there may be a conflict there - the router will try and assign IP addresses to its ports but, if the switch is being instructed already then the IPs won't be sent from the router.

In XP, pop open the Control Panel, open Network Connections, right-click the network connection (generally named Local Area Connection - ignore 1304 if it's there) and select Properties. From here, double-click TCP/IP from the list and on the new dialog ensure that the option to have the IP assigned automatically is selected and - at the bottom - the DNS server is also being assigned automatically. Ok both dialogs and check your network connection (it will need a moment to find your IP address but you can watch the progress in Network Connections).

In Vista or Win7, pop open Control Panel and where it has the option "View by" select small (or large) icons. Then, go to Network and Sharing Centre and select Change Adapter Settings from the left side of the screen. Right-click the name of your network connection (usually Local Area Connection) and click properties. Double-click the TCP/IPv4 item from the list and ensure that the option for obtaining the IP address automatically is selected, as well as the option to obtain the DNS Server automatically. Ok both dialogs and retry your network connection. This progress can be viewed in the Network Connections panel or at the bottom-right corner of Windows next to the clock.

[Tipstaff]

Out of curiosity, do you or did you have to clone the MAC address of a PC in order to get the router to work on your ISP? Also, do you have any network storage boxes that have a built in DHCP server, or as suggested, any PCs that have a DHCP server installed (in particular, are any of the computers running Windows Server)?

Have you tried disconnecting the cable from that particular PC from the switch? If not, do so at the switch end. While not really necessary, you might want to have the other PCs off before this, then turn on one of the computers. This way it'll be a fresh connection that is made to the router when you start one of the other PCs up. The primary reason for this suggestion, though, is that it will tell you whether this is specifically a problem with that PC.

Last 2 suggestions:

1) double check that no other computer has the same IP as your router, specifically that this problem computer doesn't have your routers IP. Do this by going to a command prompt, and typing in "ipconfig /all" (no quotes). On the same note, when everything is up and running just fine check that particular computers IP (including IP, Subnet, Gateway, and DNS server listings), and compare it to the other PCs. If the other PCs have that computers IP listed in the Gateway or DNS Server sections, then that means they are getting their IP, or at the very least, are directed to go through that PC in order to get onto the net. Also, double check your routers settings for the Primary and Secondary WINS listings, and check that number (if there is one) to your computers IP. It should not be the same at all (in fact it should either be 0.0.0.0, or have your ISP servers in there).

2) When in doubt do a hard reset of your router back to factory defaults. You could also uninstall, and then reinstall your network cards drivers on each of your computers. This should reset everything, including any TCP/IP or other settings back to it's default.