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I have 3 PCs at home (with Win XP, Win 7 & Win 7) and a router. I am always connected to the internet through the router (PPoE connection). My problem is that sometimes when I want to search or open a page, my browser tells me that the server cannot be reached, as if I don't have a connection to the internet. Other times it logs me out from messenger, but browsing still works. FTP download/upload also works. If i disable and enable the LAN then all works fine.

The connection doesn't always drop on all three PC's at the same time.

Anyone got any idea besides re-installing OS?


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Is this happening on one, two, or all three PCs? – Bobby Apr 7 '10 at 7:54
WHat happens if you try to ping through the router when it seems down? (start->run->"cmd"->"ping" will ping a google DNS server) – Fake Name Apr 7 '10 at 7:59
@Fake Name: That doesn't even work for me, and my connection is hunky-dory. – Paul Lammertsma Apr 7 '10 at 8:05
it's happening on all three PC's – Remus Rigo Apr 7 '10 at 8:14
Reinstalling the OS is probably not a good idea then, because if you have the problem on all PCs, the problem is with your router or your internet connection. Try connectiong with one of your computers directly to the internet, and if the problem is gone, then it's your router that's messing with you. – petersohn Apr 7 '10 at 8:43

Check DHCP settings as well; a lease that doesn't renew till the lease expires will look like a brief connection drop, and will not happen on all three machines at the same time. Normally, the client starts trying to renew the lease when it is half-way through the lease period. ipconfig /all will show the lease info, including when the lease was obtained and when it should expire. If you find that the lease was obtained right after the connection interruption took place, that would be the smoking gun.

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DHCP is always turned off – Remus Rigo Jan 2 '11 at 17:53
up vote 0 down vote accepted

I have re-installed on oll PC's the OS, it might have been a trojan or something (on all PC's). I have different AV, but none of them found anything... Now it works fine...

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