SBS 2003 SMTP email delivery issues

[ghosking]

Hi, I have recently installed SBS 2003 SP1 + all current patches and the server is working OK.

However email delivery is a little hit and miss. Messages seemed to get stuck in the Exchange queue. To assist I modified the SBS SMTP connector delivery options to always run, I also modified the default SMTP Virtual server properties under protocols and specified external DNS servers to use (including the ISP's and others). Still the problem occurs, some mail flows out OK and some gets stuck and the users get delay messages and sometimes failures. However websites like

http://www.dnsstuff.com

show that the domains are valid and MX records are retrieved OK.

Anyone got any ideas, users are getting frustrated. Could there be some external domain checking going on that I can modify?

Many thanks

G Hosking

 

[TechSoEasyMVP]

On an SBS you should NOT manually modify the SMTP Connector or Virtual Server. All email configurations are done with the Configure Email and Internet Connection Wizard (CEICW -- which is linked as Connect to the Internet in the Server Management Console > To-Do List).

A visual how-to is here:

http://sbsurl.com/ceicw

If messages are getting stuck on the outbound, then I'd check to make sure that Port 25 is not blocked by your ISP. Generally, non-commercial cable or DSL services block this port to prevent spammers from abusing their networks. Most often you can get it unblocked by calling them, but if not, you have to configure their SMTP server as a Smart Host in the CEICW.

Jeffrey B. Kane
TechSoEasy

http://www.techsoeasy.com

 

[58sniper]

I'd also check your public IP address for the correct reverse DNS entry. Go to

http://www.dnsstuff.com/

and check. Also check to see if you're blacklisted.

Pat Richard, MCSE MCSA:Messaging CNA
Microsoft Exchange MVP
Want to know how email works? Read for yourself -

http://www.ietf.org/rfc/rfc2821.txt

 

[ghosking]

Thanks for your reply, this is not my first SBS server however, I have setup SBS 2003 many times before, modifying the smtp connector and virtual server was an attempt to solve the issue, not for any other reason. If port 25 was blocked then all mail would be queued, this is not the case only some mail.

I will check the public IP address though to see if that's listed, thanks

 

[TechSoEasyMVP]

Sorry, I missed the "some" part of your initial question.