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Resolved SMTP port 25 not working?

Catia

Basic Pleskian
I have a vps running ubuntu 16.04 and Plesk Onyx 17.0.17. When I set up email accounts through Plesk (which is using postfix and dovecot) I have trouble accessing the account through the MS Outlook 2007 client. The only way I've been able to make the outgoing mail work is by connecting through port 465 using ssl. This works, but it seems odd to me.

I've got port 25 open in the firewall, I'm just wondering if I've got something configured wrong. I've tried 587 too, but that didn't work either. Any suggestions?
 
Hi Catia,

I have trouble accessing the account through the MS Outlook 2007 client
Pls. keep in mind to investigate issues/errors/problems with the help of log - files and configuration files. We are unable to guess your unique setups and configurations and we can't guess possible errors from your eMail - client.
Second, pls. don't forget, that each eMail - client might have issues/errors/problems as well... try to eliminate an eMail - client - software root cause, by using different eMail - clients. ;)
 
Thanks. I'll look around in the log an config files and see if I can find anything. So you're saying there's no port configurations or anything like that through Plesk itself?
 
Local router? If you mean the one that I use to connect to the internet, it's an xfinity gateway, I think the model is called "technicolor". If you mean the one connected to the server, I have no idea - it's a virtual server anyhow, so I don't think there is one... exactly.
 
Ok, I thought that it could be a blocking list for outgoing SMTP traffic in your router. Maybe the same in an antivirus software? Often the case with our customers.
 
I suppose something like that is possible, but I'm moving sites from an old server to this new server, and there was no problem connecting to the same domains on the old server through port 25 - that leads me to believe it's something with the way I've got this new server set up.
 
After i've found this thread i know i'm not alone...
Catia did you solved the port 25 problem?
 
Nope... I never got it working, so I just gave up and I'm using port 465 with SSL encryption. It works, but if I recall correctly Outlook complained about something the first time I set it up. Since then it's worked fine. I even upgraded to Windows 10 and the latest version of Outlook on the client end, but to no avail. It's not a huge deal for me since I'm not a reseller, but it still seems very odd. I'm sure there's some little setting somewhere on the server that needs to be changed, but I sure couldn't find it!
 
often consumer internet providers block port 25 on their network except for their own mail servers. Using the submission port is normally the solution.
 
That's not what happened to me. Same server with Plesk 12.5 perfectly working on port 25 without ssl
 
You most probably tried to send username and password over an unencrypted connection.

Modern settings of postfix does not accept this anymore. I would not try to change that in this time and age.
 
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