Responder a este mensaje

El correo electrónico funciona perfectamente si no hago el cambio en el
valor de la MTU, pero no tengo acceso a algunas páginas dentro de Internet
no importando el navegador que utilice. Si cambio el valor, puedo ver todas
las páginas pero dentro de Outlook Express ya no salen los correos, si
llegan.

Este problema lo tuve con otros equipos XP y W2K, cambié el tamaño de la MTU
y ya pude tener acceso a todas las páginas y no tuve problemas con los
administradores de correo, todo funciona correctamente.

En Microsoft encontré un documento que explica estos problemas y como
solucionarlo:

====== INICIO

Can't access some websites while using a shared PPPoE connection

Intended For
Windows XP[NL]Windows 2000[NL]Windows Me[NL]Windows 98

If you're using Windows' built-in support for Internet Connection Sharing,
and your Internet connection is facilitated by PPPoE software (such as
Enternet 300) or Windows XP's built-in PPPoE, you may experience this
problem. Although any web site will be accessible on the "Host" computer,
certain web sites will never load successfully from any of the "client"
machines. (If you don't know what "Hosts" or "Clients" are with regard to
ICS, read Internet Connection Sharing.) The problem is caused by an
incompatible MTU networking setting: Windows' default is 1500, but PPPoE
uses 1492 or 1454. Here's how to fix it:
1. Find the IP address of your gateway. If you're using Windows 2000 or XP,
run IPCONFIG at a command prompt on the Host computer. If you're using
Windows 98 or Me, run WINIPCFG on the Host computer. Either way, you'll get
an address that looks like xxx.xxx.xxx.xxx (where the x's represent
numbers).
2. Then, go to one of your Client machines, and type the following:
PING -f -l 1500 xxx.xxx.xxx.xxx
(where xxx.xxx.xxx.xxx is the gateway address you obtained in the first
step). You'll probably get an error message indicating that it must be
fragmented. If you do, type the following:
PING -f -l 1492 xxx.xxx.xxx.xxx
If that doesn't work, try this:
PING -f -l 1454 xxx.xxx.xxx.xxx
3. The numbers in each of these examples (1500, 1492, 1454) are the MTU
values. Continue issuing this command with lower and lower MTU numbers until
you get ping responses instead of an error message. The highest MTU value
that works is the one you need to be using. If an MTU of 1500 (the first
command, above) does not produce an error, then this solution won't work for
you.
The next step is to configure all your Client computers to use the new,
lower MTU as the default for all Internet communication.
Windows 2000 and XP:
1. Run the Registry Editor (REGEDIT.EXE) on one of your "Client" machines.
2. Navigate to HKEY_LOCAL_MACHINE\ SYSTEM\ CurrentControlSet\ Services\
Tcpip\ Parameters\ Interfaces.
3. There should be several subkeys under the Interfaces key; most likely,
you'll find three. View the contents of each key by clicking, and find the
one that corresponds to your primary network adapter; it will be the one
with more values than the other two, and will have an IP address value set
to something like 192.168.0.x.
4. Once you've found the correct subkey, create a new DWORD value in it
(Edit -> New -> DWORD Value), and name the value MTU.
5. Double-click the new value, choose the Decimal option, and type the MTU
value determined above.
6. Click Ok when you're done - you'll need to restart Windows for this
change take effect.
7. Repeat this for each Client machine.
Windows 98/Me:
1. Run the Registry Editor (REGEDIT.EXE) on one of your "Client" machines.
2. Navigate to HKEY_LOCAL_MACHINE\ System\ CurrentControlSet\ Services\
Class\ Net\.
3. Under that branch, find a key (numbered, such as 0005) that contains has
TCP/IP assigned to the DriverDesc value.
4. Select New from the Edit menu, then DWORD, and type MaxMTU for the name
of the new value.
5. Double-click the new value, choose the Decimal option, and type the MTU
value determined above.
6. Click Ok when you're done - you'll need to restart Windows for this
change take effect.
7. Repeat this for each Client machine.
Fuente:     http://www.annoyances.org/exec/show/article04-107/

Info relacionada:
Windows TCP/IP Registry Entries [Q158474]
Description of the Internet Protocol Packet Size Setting [Q183437]
How to Share a PPPoE Internet Connection with Windows XP [Q316276]

===== FIN

La máquina en la que tengo este problema es win98 y la opción descrita
arriba para este SO no funciona.

Gracias por su apoyo....

jo@co


-----Mensaje original-----
De: Gabriel Serazin [mailto:gaseraza@sinectis.com.ar]
Enviado el: Viernes, 29 de Agosto de 2003 12:28 a.m.
Para: consultas@usuarios.saulo.net
Asunto: Re: [SauloNet] Problema con MTU...

Fijate cómo está configurado el servidor de correo entrante y saliente del
outlook y en qué puertos están configurados dichos servidores. Si tenés una
cuenta pop3, el número de puerto del correo saliente es 25 y el del correo
entrante es 110.
Cualquier cosa, escribe nuevamente.
Saludos




____________________________

La lista de consultas y comentarios relacionados con Saulo.Net
Información, bajas y altas en http://www.saulo.net/lista/