ICS on small home network no longer works for http traffic

[Guest]

ICS small home network no longer works for http browsing just comes up with page not found message after a timeout period is reached. . Both XP PCs with all the latest updates and service packs. The dhcp aspect is working fine. The client PC can ping to a outside IP, or a name and DNS resolves the name ok. FRom the clients browser I can go go an ftp site ok. IT seems to be all http traffic from the client does now work. I have tried disabling and renabling the shared LAn connection releasing and renewing the ip config etc. Ive checked the security settings in the browser properties and all seems ok. The functionality of the ICS host is fine. Anyone any ideas ?

 

[Robert L [MS-MVP]]

quoted from http://www.ChicagoTech.net
Can't access some web sitesSymptoms: 1) If you're using MS ICS or Windows
server as router to access the Internet, your clients may not be able to
access certain web sites. However, the ICS host or the server doesn't have
this problem.
2) After installed a new router or cable modem replacing dial-up to access
the Internet, you can't access some web sites.
3) You also find that most web sites you can't access are block to ping or
they are security sites using HTTPS.

Causes: 1) The problem occurs because many web servers block ICMP messages
and the packets are dropped. As a result, the requested web site doesn't
load.
2) This problem is caused also by an incompatible MTU networking setting.
You may try to install the latest SP. If you use MS ICS, you may want to
configure all your Client computers to use the new, lower MTU as the default
for all Internet communication. To modify the MTU size, locate the following
registry key: HKEY_LOCAL_MACHINE\ SYSTEM\ CurrentControlSet\ Services\
Tcpip\ Parameters\ Interfaces. If you use a router like Cisco DSL Router,
you may want to adjusting the PPPoE MTU Size. For example, to adjusting the
PPPoE MTU Size on the Cisco DSL Router, do

interface ethernet0
no shut
ip address <ip address> <subnet mask>
ip adjust-mss 1452


--
For more and other information, go to http://www.ChicagoTech.net

Don't send e-mail or reply to me except you need consulting services.
Posting on MS newsgroup will benefit all readers and you may get more help.

Robert Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN, Anti-Virus, Tips & Troubleshooting on
http://www.ChicagoTech.net
This posting is provided "AS IS" with no warranties.

 

[Guest]

Thanks for the reply Robert. The ICS Host is a XP Pro PC
All was working fine until last friday. IP conecvity to an external IP is working fine from the ICS client as pin
works to an IP or to a www address as DNS is resolved ok. ITs as though the ICS host is not proxying the
http port 80 traffic to the ICS Client. I dont believe that MTU reg entry will make any difference

 

[Guest]

MTU change on registry worked on Windows XP Client!!! (MTU=1492, as reference from other client working OK

Hi all
I experienced exactly the same problem on a small office network with a ICS host and other clients. Apparently, ICS host and ONE client (which could surf the web without any problem) had installed WinXP SP1, but other XP client didn't, and he couldn't open any web page. For the XP client, I added the registry value MTU=1492 in the location you describe, restarted the machine and then it worked fine!! But I have other client using WIN98. I tried to do the same, but the REGISTRY ENTRY DOES NOS EXIST ON WIN98 AS ON WINXP. Can you tell me which is the equivalent for the XP registry entry on Win98 Second edition

Thanks!


----- Robert L [MS-MVP] wrote: ----

quoted from http://www.ChicagoTech.ne
Can't access some web sitesSymptoms: 1) If you're using MS ICS or Windows
server as router to access the Internet, your clients may not be able to
access certain web sites. However, the ICS host or the server doesn't have
this problem
2) After installed a new router or cable modem replacing dial-up to access
the Internet, you can't access some web sites
3) You also find that most web sites you can't access are block to ping or
they are security sites using HTTPS

Causes: 1) The problem occurs because many web servers block ICMP messages
and the packets are dropped. As a result, the requested web site doesn't
load
2) This problem is caused also by an incompatible MTU networking setting.
You may try to install the latest SP. If you use MS ICS, you may want to
configure all your Client computers to use the new, lower MTU as the default
for all Internet communication. To modify the MTU size, locate the following
registry key: HKEY_LOCAL_MACHINE\ SYSTEM\ CurrentControlSet\ Services\
Tcpip\ Parameters\ Interfaces. If you use a router like Cisco DSL Router,
you may want to adjusting the PPPoE MTU Size. For example, to adjusting the
PPPoE MTU Size on the Cisco DSL Router, d

interface ethernet
no shu
ip address <ip address><subnet mask
ip adjust-mss 145


--
For more and other information, go to http://www.ChicagoTech.ne

Don't send e-mail or reply to me except you need consulting services.
Posting on MS newsgroup will benefit all readers and you may get more help

Robert Lin, MS-MVP, MCSE & CN
Networking, Internet, Routing, VPN, Anti-Virus, Tips & Troubleshooting on
http://www.ChicagoTech.ne
This posting is provided "AS IS" with no warranties