email failures

Hi all
Hoping once again someone can be of assistance. My client is running SBS2K,
exchange server, etc and has suddenly developed a strange problem. There is
a specific email provider that they are unable to send mail to. They can
receive mail from two individuals but get immediate mail failure when either
replying or creating new e-mails. The mail host is snet.net They get mail
from abc123@snet.net but cannot return mail to them. I have contacted SBC
tech support (no luck) and have sent mail to their web services host but
haven't heard back. Can anyone shed sodme light??

thanks
CarlS

John
Mon Aug 16 09:46:18 CDT 2004

Can you post the NDR you get back when the mail fails to deliver?

--
John Oliver, Jr.
MCSE, MCT, CCNA, Exchange MVP
Microsoft Certified Partner


"Carl Stockwell" <cstockwell3@yahoo.com> wrote in message
news:ObHAIbTgEHA.1764@TK2MSFTNGP10.phx.gbl...
> Hi all
> Hoping once again someone can be of assistance. My client is running
> SBS2K,
> exchange server, etc and has suddenly developed a strange problem. There
> is
> a specific email provider that they are unable to send mail to. They can
> receive mail from two individuals but get immediate mail failure when
> either
> replying or creating new e-mails. The mail host is snet.net They get mail
> from abc123@snet.net but cannot return mail to them. I have contacted SBC
> tech support (no luck) and have sent mail to their web services host but
> haven't heard back. Can anyone shed sodme light??
>
> thanks
> CarlS
>
>

Brad
Thu Sep 09 16:30:07 CDT 2004

The mail system you are sending mail to may have implemented Reverse DNS
lookup which can cause problems. If you are being NATTED by your provider
there may be an issue... We had a similiar situation. Lots of time it is
implemented to reduce SPAM - but it also can cause mail delivery issues for
lots of people. There's really not much you can do - unfortunately.

Brad


"Carl Stockwell" <cstockwell3@yahoo.com> wrote in message
news:ObHAIbTgEHA.1764@TK2MSFTNGP10.phx.gbl...
> Hi all
> Hoping once again someone can be of assistance. My client is running
SBS2K,
> exchange server, etc and has suddenly developed a strange problem. There
is
> a specific email provider that they are unable to send mail to. They can
> receive mail from two individuals but get immediate mail failure when
either
> replying or creating new e-mails. The mail host is snet.net They get mail
> from abc123@snet.net but cannot return mail to them. I have contacted SBC
> tech support (no luck) and have sent mail to their web services host but
> haven't heard back. Can anyone shed sodme light??
>
> thanks
> CarlS
>
>