Showing results for 
Search instead for 
Did you mean: 

SBS2000 - Exchange and SMTP Config


SBS2000 - Exchange and SMTP Config

Please help a newbie here.....

Under SBS2000 the Internet Connection wizard asks 2 things regarding the Exchange setup...

1. Forward all mail to a Host or use DNS. I have selected forward all mail to
2. Issue a TURN command which I have selected.

I have also enable the SMTP on the email settings under

Will this work? As I can recieve email, although when I send email it just gets stuck in the "Messages with an unreachable destination" folder under the SMTP connector queue...

Please help me

Moderators note (John) I have moved this from the ADSL forum as it doesn't seem to be just ADSL related.

Exchange 2000 setup

I might be wrong but shouldn't the host be
Rising Star
Posts: 269
Thanks: 33
Fixes: 1
Registered: 10-08-2007

SBS2000 - Exchange and SMTP Config

You can use either option.

Sending mail
1. With DNS the mail exchanger is resolved for each message and the message is then sent directly to the target domains mail server. This system is faster and does not rely on your ISPs mail server. You should avoid this method on dial up links though. DNS must be configured on the exchange server to correctly resolve external names.

2. With forward to single host (relay or smarthost) all mail is sent to the relay server which then delivers using DNS. This method is slower as mail is first delivered to the relay before onward delivery is attempted. Delivery is dependant on the relay server being available and at busy times messages can be delayed.

You can specify the relay server by IP or domain name. Generally you use the domain name. To use the domain name the server must be able to resolve external names. But there are specific circumstances when you do not want your exchange server resolving external names and you must specify the relay servers IP. Using the IP is fine until the ISP changes the address and mail delivery stops for no apparent reason.

AOL has blocked delivery from huge swathes of broadband IP ranges. They may not accept mail sent directly using DNS. In this case you can send all mail via the relay or define a separate route.

Recieving mail (SMTP)
Similar to sending you can recieve mail either directly or via a relay.

If you have a domain name and fixed IP you can configure your mail server as the mail exchanger (MX) in the Internets public DNS. The advantage is again speed and the lack of dependance on the ISPs relay servers. MX records include a priority number so that mail can be sent to a fallback server if the primary server is offline. Generally you specify your ISPs relay as the secondary server and set up a scheduled retrieval trigger.

The standards method of retrieving mail from a relay is to send a TURN or ETRN command. But few ISPs use TURN or ETRN as it can lead to some serious routing problems. Different ISPs use different methods to trigger retrieval. require a finger command to be sent to
With Exchange 2000 a single line batch file can be scheduled to issue the finger command.

If you allow mail to be delivered directly to your Exchange server you must ensure that the your Exchange server is configured to reject SPAM mail. By default the Exchange server will allow SPAM to be relayed which will result in the server being added to a SPAM blacklist.
Publishing your mail server address in the public DNS will attract SPAM and hackers. The network must be adeqately protected from outside intrusion.
You can also use POP to recieve messsages on SBS2000 but it is not part of this discussion.

The Simple Way
If you do not know what you are doing:
1. Configure the server to relay outgoing messages to
2. Schedule an hourly batch job to issue a;
3. Do nothing else

If you still can not send or recieve you may have a network / firewall problem.