SMTP webconnector not working

[vimalthehero]

we are looking for advice on below Qliksense webconnector issue on SMTP connector.

it keeps throwing error even though providing proper email address and SMTP server details for test connection.

Failure error message :

One or more recipients rejected. Call SmtpException.GetRejectedRecipients() to get a collection of rejected email addresses.

Thank you for your reply in advance

[Vegar · Accepted solution]

It could be limitations on the smtp server? Have you checked your smtp fire wall or if you need to add your Qlik WebConnector server as a white listed IP in you smtp configuration? What about your user access? Are your user allowed to send emails? Are you sending emails to different domain as your smtp? Sometimes there are limitations on the smtp only accepting internal emails as default.

[Jay_Brown]

I agree with @Vegar here.  This is likely an SMTP relay or firewall issue, especially if there has been no additional configuration there.  You can test this by using a test instance of another tool such as SMTP4DEV which will emulate a mail server and help you rule out the Qlik Web Connector as the culprit.  If you have not configured the SMTP relay as of yet, I would start there.

[vimalthehero]

we had requested for firewall exceptions to be made, will soon be updated on this issue

[vimalthehero]

SMTP not working issue fixed, Firewall exceptions implementation made this working fine..

[Vegar]

@vimalthehero 

That's great to hear

Thank you for the feedback. 

[pannacheworld]

SMTP WebConnector in Qlik Sense Not Working – Rejected Recipients Error

Hi Community,

We are currently facing an issue with the SMTP WebConnector in Qlik Sense, and we're hoping to get some guidance or a solution.

Issue:
While trying to send a test email via the SMTP WebConnector, we are consistently getting the following error:

Failure error message:
One or more recipients rejected. Call SmtpException.GetRejectedRecipients() to get a collection of rejected email addresses.

Despite providing valid SMTP server details and a correct, active email address in the test configuration, the connection keeps failing with the same message.

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Steps we’ve already checked:

• The SMTP server details (host, port, SSL/TLS settings) are correct

• The sender and recipient email addresses are valid and active

• Tried multiple email addresses from different domains

• SMTP server is accessible and not blocking connections

• No firewall or spam filter issues on our mail server end

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Questions:

1. Is there any specific format or requirement for the recipient field in Qlik’s SMTP WebConnector?

2. Could this be related to authentication or sender domain mismatch issues?

3. Are there any additional logs or ways to call GetRejectedRecipients() from Qlik's end for debugging?

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Any guidance or suggestions to resolve this error would be greatly appreciated.

Thanks in advance!

[vimalthehero]

We've seen this issue before—it was due to firewall, and our IT team fixed it by adding exceptions. hope it works for you too