Need Help With Intermittant Disconnects...

We have been troubleshooting a problem with intermittant internet disconnects the past few months - have determined that the Modem is not the problem - and have tried 3 different Routers (D-Link DI-604, Linksys WRT-160N and currently D-Link DGL-4500) resulting in no change to the problem.

Now, the only other component that is common to all of our computers is NOD32 - and it has been suggested to us that there may be a setting that is causing these random disconnects.

WIRED directly to the router: 2 Dell XPS Desktops with VISTA Ultimate and Outlook 2007, 1 HP Tablet with VISTA Home and Outlook 2003.

WIRED through D-Link DGS-2205 Switch to the router: 1 Gateway Laptop with XP Home SP3 and Outlook 2003, and Brother MFC-9840CDW Printer.

NO wireless is enabled. All computers and printer have most recent updates applied. NOD32 has the most recent update.

All computers are experiencing intermittant - many times per day - disconnects from the internet, and email will not send (stays in the outbox).

The DGL-4500 is updated to v. 1.13, changed MTU to 1452, disabled DNS Relay (per TS).

Have been keeping logs, if that will help identify any issues...

Would very much appreciate help with this very frustrating and time wasting problem - our home based office comes to a halt several times per day, when we have to do "Repair and Diagnose" in VISTA to get the connection to come back on. (Embarq tech thought that was a clue pointing to a possible conflict within NOD32) In order to get emails out of the outbox, we have to close out of Outlook, then re-open it to force the mail out...

The Embarq 660 Modem has been 'thoroughly' troubleshooted by their techs, with no problems found - and if we connect any of our computers directly to the Modem, there are NO disconnects...

Are there any settings in NOD32 that we could adjust to fix this? Help with this problem would be very much appreciated...

 

I think I have the same problem too. When my network activity is high, I'm receiving BSOD screen or network traffic just freezes. PPPoE connection is active and not disconnects, but I can't send any e-mail or download something, or browse web pages, just like if my connection is off. When I'm trying to open connection menu and reconnect, it also freezes. Only reboot helps in my situation.

 

Are you running torrents or P2P applications? Programs like that flood the NAT table on consumer-grade routers which makes them drop connections and act flaky. If it is an issue with Nod32, you should be able to disable the Web access protection module on the systems temporarily and see the symptoms go away.

 

I do use uTorrent. When you said NAT, I remembered one option, (Enable NAT-PMP port mapping) that I disabled after uTorrent installation. Could it be the reason of trouble?

 

No, that is basically Apple's proprietary uPNP implementation. Your routers don't support it so the setting doesn't really do anything for you. Stop running the torrents for a few days and reboot the router, see if things stabilize. If they do, then it pretty clearly points to the NAT table getting flooded in which case you can either re-configure uTorrent so fewer simultaneous connections are allow and fewer active torrents, or install 3rd party firmware on one of the router (DD-WRT or Tomato) that will allow you to dedicate more memory to the NAT table and lower the expiration timeout for entries. Or set up one of your computers to do the routing and DHCP (the networking wizard in Windows makes this pretty easy) which won't have the memory limitations of a consumer-grade router.

If stopping the torrents doesn't help, then I would try disabling modules in Nod32 and going from there.

Edit: Sorry, didn't see who I was responding to. My advice still applies in your situation for the network traffic freezing. As for the BSOD, a memory mini-dump would be helpful to diagnose that. The most likely cause of that is bad ram so I would try running a Memtest+ pass or two to rule that out first.

 

Thinking that some of the responses may have been to the subsequent posters - we are not knowingly running 'torrents' or 'PnP' - can you provide more description of those... ?

SmackyTheFrog - can you sort out the response... ?

We are NOT getting BSOD - please see original post - thanks...

 

Thanks LowWaterMark - we are getting worn out by dealing with this disconnect problem for many months, so we would like to continue this thread and hope to have some of the eset administrators respond to these potential settings issues...

What could be causing intermittant internet disconnects... ?

There are so many settings available in NOD32 - do we need to try changing some setting to get this problem solved... ?

Please read the original post for our details - thanks...

 

2ATtheBus, please check your PM for a possible OT solution.

 

As I said in my original response, your first step here should be temporarily disabling the http filter module to see if the behavior changes. Your step of connecting computers directly to the modem and not seeing the problem really points this to being an issue with the routers you are using or a common failure component that the routers are using, like a bad electrical socket that is causing it to lose power and reboot or a bad patch cable between the modem and router.