PC network weirdness

Maybe there are two problems, the existing flaky DSL that you characterize as "not totally unusual" and a separate issue with ZoneAlarm and the most recent MS update?

Zonie didn't like the behavior of a file that the MS update changed and it blocked all "internet" access while allowing "local zone" to proceed as usual. That problem was fixed pretty quickly with a ZoneAlarm update.

Do you have Zone Alarm? A week or so ago after an automatic Microsoft update, millions of computers could not access the net, including mine. Some Zone Alarm firewall and MicroPants software issue.

If you have Zone Alarm, go to their website and there is info on fixes.

Gareth.

But if you have no net access you can't do that can you. Oops.

When I first rang my ISP about no Interweb, the chap advised me to uninstall Zone Alarm as he had suffered the same problem!. I did and immediately got my Net access back. I quickly downloaded a Free Antivirus to cover my arse. However, I couldn't find out how to download Zone Alarm again. The key I have will only fit the version it is designed for, and trial versions couldn't be switched to the Pro version I had paid for. I sent them an email and several days later got a pointer to the reinstall thingy, with the advice to Save to the hard drive rather than jut run it. This is it.

What a palaver that was, I can tell you.

Gareth.

I had a similar problem (Lan worked but no internet access, happened overnight) when my ISP changed hands, hours spent with online help finally got me to someone helpful who suggested I needed to release/renew the IP address due to the company changeover and subsequent maintenance with their equipment.

Sam, I have no idea what causes this symptom, but I have a friend with a PC that does the exact same thing (except he has a cable modem instead of DSL). I went over to fix it and left totally stumped. We replaced the NIC for the same reason you did but no change. We even reinstalled Windows (but did not totally wipe the HD) with no change in symptoms. Since the PC in question was fairly old and he was looking for an excuse to upgrade, we gave up. But, it bothers me to have never figured out the root cause. Let us all know if you figure it out.

Regards, Pat

If you have a SPI capable router using NAT, and are aware of what programs (including adware/spyware) are running on your computer, you don't really need ZoneAlarm or any other additional firewall software above Microsoft's...

Sam:

If your machines can talk to each other and the router, either your DSL modem (you swapped that out already so nix that) or a problem with your ISP. Talk to them, they can check the DSL port at their CO and make sure it's passing traffic. Your hardware is functioning perfectly. Do you get a a "LINK" light on the ADSL modem for the DSL line?

Dave

You didn't say which OS? I wonder if your ISP changed your IP? Can you check "gateway" setting in router?

Not sure about Sam's case, but in my similar case, other PC's on the network could get to the Internet. ...Pat

Sam,

You should fix your .sig. The first line of your .sig needs to be a "-- ". Thats is: just 2 dashes and a blank - _nothing_ else.

Without that, everyone's followups to you include your (already too long) .sig and make a mess in trying to read the thread -- that is, unless they are clever and kind enough to trim their followups.

Regards, Jonesy

Can you ping the gateway? Does the questioned PC get an address from the DHCP server?

Could be one of those.

My first hunch would be, try a new known-good Ethernet cable or three. I've seen Ethernet cables go bad (both home-made and commercially- bought) when one of the pin-to-wire crimp-on junctions went intermittent due to oxidation or flexing stress or old age or a contrary nature. The resulting misbehavior can be extremely frustrating, as the failures are sometimes intermittent, sensitive to packet length and content, sensitive to what machines the cable is connecting, the switch port, etc.

Another datum: my DSL-router/firewall/mail-server system in the garage recently stopped talking to the rest of the systems in the house, for no apparent reason. Switch connectivity looked good, activity lights blinking, but no actual packet traffic.

It turned out that the switch had stopped forwarding packets... its internal bridging engine had apparently crashed. Power-cycling it fixed the problem... for about a week, and then the problem recurred... again, power-cycling the switch cleared the fault.

I retired the switch and the problem hasn't come back.

Chasing down these sorts of problems is often an exercise in "substitute, swap, see when/where the problem moves or goes away."

Thank you! That was exactly it. Even though I had disabled ZA the first thing I tried and rebooted that way, it didn't help so I didn't think ZA was the problem. But the interaction with MicroShaft software, anything's possible! It seemed like updating ZA alone fixed the problem, but I uninstalled the MS patch anyhow.

--- sam | Sci.Electronics.Repair FAQ:

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Fortunately, I have multiple PCs and since the LAN worked, I could transfer the ZA update easily enough. :)

Aren't PCs wonderful? I hate PCs, and laptops even more. :)

Cheers!

--- sam | Sci.Electronics.Repair FAQ:

Important: Anything sent to the email address in the message header above is ignored unless my full name AND either lasers or electronics is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs.

Yeah, both my router and DSL modem have ALL kinds of features I haven't the slightest clue about! :)

Zonealarm has been good to me so I stick with it. :)

Was the information on the ZA/MS interaction sent as an email advisory? I'm supposed to get those.....

--- sam | Sci.Electronics.Repair FAQ:

Important: Anything sent to the email address in the message header above is ignored unless my full name AND either lasers or electronics is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs.

Yes, I should have noted that only the one PC couldn't get to the Internet. And it was the ZoneAlarm/Microsoft patch problem.

Thanks to all who replied.

--- sam | Sci.Electronics.Repair FAQ:

Important: Anything sent to the email address in the message header above is ignored unless my full name AND either lasers or electronics is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs.

The weird thing is that I disabled (e.g., took it out of the startup list) ZoneAlarm but that didn't fix the problem. But installing the update did.

--- sam | Sci.Electronics.Repair FAQ:

Important: Anything sent to the email address in the message header above is ignored unless my full name AND either lasers or electronics is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs.

I didn't get anything.

If you are using Zone Alarm I would seriously start considering this to be the cause of your problem, unless you have done something to fix it. My network was fine, other computers without Zone Alarm could access the Net, mine with Zone Alarm could not.

Gareth.