Reasons for SMTP+ messages not being sent

When you are using SMTP+ and messages do not get sent, the reason is typically one of the following. Please check to see if any of these apply.

Possible reason	What to do	Other comments
The user name and password of the SMTP+ user are not correct	Log into your admin console Retrieve the SMTP+ credentials for that user Re-enter them in the email client that is sending the messages	None
The sender's domain is not one of the authorized domains.	Log into your admin console Review the details for the SMTP+ user that you are using Make sure that the domain that you are using is authorized	You will typically need to enter a second-level domain, since email addresses are typically at the second level. That is: you will typically enter mycompany.com and not www.mycompany.com You do not "need" to authorize at the domain level. You can authorize specific email addresses. It's whatever works best for you. See below.
The sender's email is not one of the authorized emails.	Log into your admin console Review the details for the SMTP+ user that you are using Make sure that the sender email that you are using is authorized	You do not "need" to authorize specific email addresses. You can authorize entire domains. It's whatever works best for you. See above.
The port used is not "open" in the Web server where the message is being sent.	Try another port. For example, if you had to specify a port in the email client and you entered port 25, try changing that to 2525 (or another port supported by SMTP+). If nothing works, ask your server administrator which ports can be used.	SMTP+ supports a variety of ports: 23, 25, 26, 587, 1025 - 5000 (limits included)
The port used is not supported by SMTP+	SMTP+ supports a variety of ports: 25, 1025 - 5000 (limits included)

Getting an alert when there is a problem

In the Alert center (Settings > List settings > Alert center) you can configure an alert that is sent to you via email when there is a problem delivering a SMTP+ message. The message that is sent to you should contain details on why the message could not be sent.

However, please note that if the issue that you are experiencing is #4 above (the port is not open on the server), the message will have never left the server and therefore MailUp will never know about it. In that case, no alert can be sent as MailUp simply does not know of the message.

Other issues

Issue

What to do

Unable to send pictographs / symbols in subject line

If your sending client does not support special characters in subject line, you can manually set the correct encoding. This is the format:

=?utf-8?Q?This is the subject text?=

Then to insert a symbol, enter his code (list of codes) and remember that each font can represent only a subset of all possible symbols. For example to insert a ♥ the subject needs to be:

=?utf-8?Q?I love you =E2=99=A5?=

It will be rendered as: "I love you ♥". Before the final emailing please test your subject with different clients, for example using Email Analysis. Check the RFC reference for further information.