SMTP Problems on exchange server

[boogster]

We have a problem at the school that has just surfaced. Every user when sending emails gets a bounce back message of:

 

The following recipient(s) could not be reached:

 

xxxxx.co.uk on 15/09/2011 18:59

There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.

 

They can send to each other internally and can receive emails no problem, can anyone please help with some advise and hopefully a resolution

 

Thanks

[bodminman]

what do the exchange server logs reveal?

[m25man]

https://www.testexchangeconnectivity.com/

 

Is your smtp service running?

 

Sounds like your upstream relay is refusing your connections.

[boogster]

Hi bodminman

are you talking about logs in MDBDATA

[boogster]

SMTP service is running and I have just restarted with no effect

[boogster]

ran test and said outbound smtp was succesful

[achedgy]

What version of exchange are you running?

[m25man]

SMTP relay behavior in Windows 2000, Windows XP, and Exchange Server

 

If your external relay is good then it has to be something you have changed on you own config.

 

Do the telnet tests first.

[boogster]

Exchange 2003 6.5sp2

[boogster]

Our DNS and ECC have just recently been transferred over from synetrix to atomwide, would this have anything to do with it as smtp connector still set to outbound1.equinoxit.net

 

We have not changed any settings at all on the server

[sukh]

1. When did this change take place?

2. Do you have a different smarthost that you have to use now?

3. Do you use DNS to send email or smarthosts?

4. Are your PTR records setup correctly?

5.SPF records?

[boogster]

1. When did this change take place? The change took place over the summer holidays and all was Ok until this week

 

2. Do you have a different smarthost that you have to use now? I have not been told to make any change to the smtp connector although I dont know why as this is still pointing to synetrix who have released everything to atomwide

 

3. Do you use DNS to send email or smarthosts? how do I find this out?

 

4. Are your PTR records setup correctly? do I need to add anything here or leave as was

5.SPF records? ??

 

 

Thanks

Edited September 15, 2011 by boogster
update

[sukh]

1. Check on your SMTP connector to the internet to see if there is a smarthost specified or not? Or are you using DNS to send emails?

2. Check on the SMTP virtual server to see if there is a smart host specified there?

3. If the Exch server that send out emails hasn't changed and the IP (public facing) hasnt changed then yu shouldn't need to worry about your PTR and SPF records.

4. Up the protocol logging for SMTP and then PM or post the results here. - Logging the SMTP Service

5. Can you also PM the entire NDR?

6. Also, is the for every sender sending to ANY External SMTP domain? Or some domains?

 

Thanks

Sukh

[boogster]

Thanks for help guys, it turns out that they failed to tell us the new smtp connector address and was still pointing to old one and they finally switched that off. All up and running again thankfully

[sukh]

Thanks for help guys, it turns out that they failed to tell us the new smtp connector address and was still pointing to old one and they finally switched that off. All up and running again thankfully

 

SMTP connector address or smarthost?

[boogster]

SMTP Connector address