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SMTP not working for ONE customer

F

ferrisr

Guest
i have 10 customers on one plesk server, and one of them can't use SMTP. I see nothing in the logs. Which logs are for SMTP? Nothing in maillog or anything. His POP3 works fine, and everybody else's mail works fine. This is baffeling me.
 
What error is he getting?? Does he smtp authentication turned on?
 
I have the same experiences with some of my customers. In each case, they are using either Microsoft Outlook or Microsoft Outlook Express.

They are different customers using a LAN infra-structure. The funny thing is that in the LAN, some of them can use the SMTP and some cannot after the Upgrade from 7.15 to 7.16 and later to Reloaded 7.51. It is strange.

The error generated from the Outlook or Outlook Express is:

Your server has unexpectedly terminated the connection. Possible causes for this include server problems, network problems, or a long period of inactivity. Subject 'Re: Various', Account: 'mail.domainname.com', Server: 'mail.domainname.com', Protocol: SMTP, Port: 25, Secure(SSL): No, Error Number: 0x800CCC0F

There is no error on the server log.

Any idea?
 
Does your clients IP show in the maillog? If not, he isnt reaching the server, if so, it could be your firewall causing problems. Paste a sample of the maillog when he actually manages to connect - 10 lines around him.
 
no log on him connecting. He tried with thunderbird AND opera. Opera just fails silently while thunderbird gives him connection errors. Can't be a firewall problem, it works for everybody else.
 
If he doesn't show in the logs it'll be either an issue local to him (his firewall or antivirus perhaps), or a network issue between him and your server.

Check traceroutes and his local pc.
 
Check with customers to make sure they are not on SBC internet. SBC is blocking port 25 through out all there servers. Not all SBC customers are blocked but it looks as if they will be very shortly if they are not blocked yet. This has nothing to do with anyone's firewall settings.
 
I have found that error to be the customers ISP. They are blocking port 25 and the customer will need to use the ISP's SMTP server. It is OK for them to use your POP address.
 
Originally posted by nero0247
I have found that error to be the customers ISP. They are blocking port 25 and the customer will need to use the ISP's SMTP server. It is OK for them to use your POP address.

I use SBC and was having the same problem sending mail. I changed the SMTP port in my email program to be 465 instead of 25 and it now works.
 
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