smtp 535 error

[#1]

Hi. Ive been trying to setup a program that sends me email notifications. Unfortunately this has led to a 535 error on my smtp. I tried to talk to plusnet on the phone but he didnt understand what i was talking about and wanted to use my phone remotely. I have tried to send an emails from outlook and they are not getting though, The outlook settings have not been changed.

[#2]

What program are you trying to set up? The 535 error is because you are entering the wrong credentials.

[#3]

That is one possibility - there are others, it all depends on the qualification of the 535 error message.  The credentials could be correct, but there have been too many failures or the IP address has been black balled.  Mention of a phone could imply that this is on a mobile network.

Not enough information here to offer guidance.

A too many failures condition will lead to Outlook also failing (to send) if connecting over the same network.

[#4]

Understand, @Townman but as the OP seems to have disappeared into the ether, despite my relatively quick response...

[#5]

Thank you for the quick reply. And apologies for the late one, I had to take my son into town.
I am trying to setup a programme that sends me a notification of an event to my mailbox, its not a email client. I know it can be done because ive done it in the past. It asks 
smtp_server = relay.plus.net
smtp_port =465 (tried 25 and 587)
smtp_authentication = SSL. (tried TTL and None, dont have the option for starttls)
smtp_login = adkin
smtp_password = ****password**
ive tried the settings that ive used before and ive checked on the net BUT i now get an error 535, b'...authentication rejected and after a few more attempts it says too many errors try later.
I then checked in outlook and tried to send a email to myself and i cannot send out but can receive. As you said it sounds like my account has been black balled, what to do?

[#6]

You have described precisely what I suspected - the un-named application has failed multiple times to the point of too many attempts… and then ALL access to the SMTP service becomes blocked for a while.

Elsewhere around here there are two threads relating to a broken back up application which needs a fix to its email module. Is this by chance the same product?

[#7]

The software is called Radiosonde auto RX ( found on github https://github.com/projecthorus/radiosonde_auto_rx)  . It Tracks weather balloons and email notifications are sent regarding new detections, and landing locations. The configuration page here https://github.com/projecthorus/radiosonde_auto_rx/blob/master/auto_rx/station.cfg.example line 356 to 416 is where these settings are.

[#8]

If the program is ALWAYS running on a machine connected to your home broadband ( wired or wireless ) , then you shouldn't need to use authentication.

smtp_authentication = None

and probably set the following

smtp_login = None
smtp_password = None

You probably need a valid email address in the Source

from = sonde@<youraccountname>.plus.com  ( assuming you are using PN email address and not a domain address )

also set smtp_port = 587

[#9]

Im getting "(535, b'Too many SMTP auth failures. Please try again later.')" 

I will try later

[#10]

I'd leave  trying with the program until you can sucessfully send using Outlook. That will confirm that the temporary 'ban' has been lifted.

[#11]

One issue has been rectified, i can now send out emails from outlook. I now need to work out what settings this notification service for the programme without  doing too many tries too frequently

[#12 · Accepted solution]

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@MisterW wrote:

If the program is ALWAYS running on a machine connected to your home [PLUSNET] broadband ( wired or wireless ) , then you shouldn't need to use authentication.

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So long as there is no VPN involved!

@digitaldan

Does the application produce a diagnostic log?

We have seen another product behave like this recently.  It was suggested that product did not have issues with an @gamil.com address ... however eventually that vendor produced a new email library and the issues disappeared.  In their case the issue was not present in their 2022 product but was present in the 2023 and 2024 versions.

The reason for sharing that is so that you do not assume unquestioningly that the issue is with the known settings - it could be the product.

Encryption

You MUST use SSL or TLS if you specify port 465.  Use of this port is deprecated and is only for encrypted connections.

Try port 587 with NO ENCRYPTION until you get this working.

[#13]

used 587 no authentication just relay.plus.net, and the software requires smtp login and password in the fields and is  now working ( and out going email in outlook. All sorted. THANK YOU.

[#14]

Moderator's note by Mike (Mav): The fix has been changed to @Townman as per message #12.