Broadband http dies after 5 minutes

[scaryjeff]

I have this problem on two comepletely seperate networks, one is using ADSL and the other cable, and with two different routers (one netgear, one belkin). The broadband connection works perfectly in every way, except for after about 5 minutes of use, no website will load, even though msn or p2p software stays connected and working. I know that the correct MAC addresses are registered, because if they are not, the connection will not work at all. Has anybody got any idea what might be causing this to happen? Resseting the router will give another 5 minutes usage before it breaks again. I'm not sure what other information would be useful.

 

[Fiveohhh]

Could be a possible DNS problem can you ping an actual external ip address when it "quits" working?

 

[PowerEngineer]

This probably isn't your problem, but I was having the same sort of behavior for a while.

Turns out it was Intrusion Detection feature on my Norton Internet Security package. I kept getting messages that it was picking up "invalid TCP flags", even from trustworthy sites like Yahoo and Anandtech. I just tried ignoring them, but after a few minutes my internet connection seemed to grind to a halt and wouldn't load new pages from these web sites. I finally found out that Norton starts blocking traffic from sites after it detects some number of "intrusions" from that site; the blocking remains in effect for a long time (20-30 minutes?).

I never could find out exactly what an "invalid TCP flag" is, but my problems went away as soon as I disabled that "invalid TCP flags" signature.

Good luck

 

[tracerbullet]

Sounds suspiciously like what I'm having right now too, and just posted about under the title "can't sustain an internet connection".

For me, and what may be true for you, I lose anything http after about 5 minutes or so. Meaning no basic web surfing. However, email (POP3), news (NNTP), and secure web sites even (https) all continue to work fine. So my first question is - once it stops working, and you can't surf, can you still get e-mail downloaded (through like Outlook or something similar of course, not through a web based)? Or, before it goes down, bookmark a secure page - something like paypal, or an online bank account. Once the connection breaks, try to reach that site. Can you?

If this is the same deal as what you have going on, perhaps we can pool resources. If not - hope it helped at least a little.

 

[scaryjeff]

Thankyou for your replies. I won't be able to test the theories out until this evening but I will write another reply when I have done so.

 

[tracerbullet]

My answer turned out to be not too difficult. I had recently reloaded Windows from a ghost image file made many months ago. Sometime before that image was made, I had in fact installed Zone-Alarm (I had posted earlier that I had not). It was turned off under both the services and the startup tabs in msconfig, and for all intents appeared to not be running. Well, somewhere, somehow, part of it WAS running in the background. And after 5 minutes it cut off my http connection. I have no idea why, but it was.

So, I reinstalled ZoneAlarm (I suppose I could have uninstalled it as well) and everything has been running perfectly again.

Good luck on yours!

 

[scaryjeff]

OK, I wasn't able to try it today because I had too much work to do. This zonealarm/norton solution sounds likely though. Thanks