phpBB3 SMTP server settings



Need help with my phpBB3 (3.1.10) SMTP setup.

I noticed that e-mails sent to and are simply not sent using:
ACP > General > Email settings:
Use SMTP server for email: No

I guess this is an issue that these providers simply block emails from DH servers, right?

So I changed this into my DH email account data.
ACP > General > Email settings:
Use SMTP server for email: Yes
SMTP server address: (my DH mail server)
SMTP server port: 25
Authentication method for SMTP: PLAIN
SMTP username:
SMTP password: password

As server address, I tested …

As server port, I tested … 25, 465, 587

As authentification method, I tested … PLAIN, LOGIN

I tried more or less every possible combination of all of the above. There’s never any e-mail arriving!

What am I doing wrong?



Ah, sorry to hear that. I just went through a similar battle to find an acceptable combination for a test site I’m setting up. So… what worked for me was

smtp_server: # make sure you have the right server, find it on

smtp_port: “587” # not 465

smtp_user: “stefano@your” # make sure you’re using the full domain name
smtp_password: #make sure you got the right one! I went nuts for a few hours before I realized I was copying-pasting from LastPass the wrong entry

Also, authentication on is PLAIN, STARTTLS true.

Triple check and let us know if that doesn’t work. Check the error logs of your phpBB, maybe increase verbosity to find out exactly what’s going on.


Thanks a lot !!!

This works:
Use SMTP server for email: Yes
SMTP_port: 587
SMTP_authentication: LOGIN
SMTP_password: password

This works as well (Yes, with 465 it works as well!):
Use SMTP server for email: Yes
SMTP_server: ssl://
SMTP_port: 465
SMTP_authentication: LOGIN
SMTP_password: password

I believe I should give 465 preference, right?

Besides that, why does my regular SMTP server not work with phpBB when configured?

Also … why don’t emails to and domains ever arrive?
DH or remote provider SMTP server configuration fault?


… later …

Just to complete this subject when mutt is used. Both works …


... set smtp_url="smtps://" set smtp_pass="password" ...

... set smtp_url="smtp://" set smtp_pass="password" ...
If the user containes a @ (like DH requires), it also works. Don’t use quotes to include the user. Just type as shown above.


Dreamhost gets pretty routine blacklist inclusion. At the moment sub5 is blacklisted by “Ospam” an organization I know nothing about and didn’t Google. My point however is use check known mail server blacklists.


But IMHO, this site ( show why emails to and don’t arrive when using my regular SMTP server. Or did I miss something?

Also, what are the differences between the sub[345] and “my” SMTP servers?

#6 points to the same IP as whichever mail server you have -> sub[345] or In the days when most connections to mail servers were not encrypted the hostname worked fine, in today’s world you likely want TLS and using the “mail.” name will render a certificate warning or error.


Ok, understood.
Thanks a lot for the explanations!