<![CDATA[SMTP - Notification has been enqueued]]>I'm using version 4.5.0

I've created an SMTP notification channel with below parameters:
Server=smtp.mailgun.org
RetryCount=1
Port=25
TLSMode=NONE
LocalHostName=localhost
FromName= xxx.mailgun.org
FromAddr=xxx.mailgun.org
Password=<password given by Mailgun>
MailEncoding=utf8
IsHTML=no

I get Status=Failure, Error message=Driver error in Send Notification test. Mailgun parameters are OK. I have tested email delivery using Windows PowerShell.

Please help.

]]>https://forum.netxms.org/topic/8225/smtp-notification-has-been-enqueuedRSS for NodeFri, 13 Nov 2026 07:21:44 GMTThu, 31 Jul 2025 10:26:44 GMT60<![CDATA[Reply to SMTP - Notification has been enqueued on Thu, 07 Aug 2025 10:05:01 GMT]]>(56: response reading failed (errno: 0)) - this means that we did not get some response from the mail server that we expected. "we" is actually libcurl that is used in NetXMS to work with SMTP. 
Since you use TLSMode=NONE which means that communication is unencrypted, you can install Wireshark and check what exactly communication is happening with the server. But it could be that server expects TLS, you can try other settings of TLSMode (and port)

]]>https://forum.netxms.org/post/34736https://forum.netxms.org/post/34736Thu, 07 Aug 2025 10:05:01 GMT<![CDATA[Reply to SMTP - Notification has been enqueued on Fri, 01 Aug 2025 06:47:44 GMT]]>Log:
2025.08.01 12:09:09.879 *D* [nc                ] SendNotification: sending message to "xxx@gmail.com" via channel "Mailgun"
2025.08.01 12:09:09.879 *D* [nc                ] Message to "xxx@gmail.com" via channel "Mailgun" dequeued
2025.08.01 12:09:09.879 *D* [ncd.smtp          ] Sending mail with url="smtp://smtp.mailgun.org:25", to="xxx@gmail.com", subject="subject4", login="xxx@sandbox8c26de1c85dc4de393a343a6f9f8f6c8.mailgun.org"
2025.08.01 12:09:53.415 *D* [ncd.smtp          ] Call to curl_easy_perform("smtp://smtp.mailgun.org:25") failed (56: response reading failed (errno: 0))
2025.08.01 12:09:53.415 *D* [nc                ] Driver error for channel "Mailgun", retrying in 30 seconds, 2 retries left
2025.08.01 12:10:23.415 *D* [ncd.smtp          ] Sending mail with url="smtp://smtp.mailgun.org:25", to="xxx@gmail.com", subject="subject4", login="xxx@sandbox8c26de1c85dc4de393a343a6f9f8f6c8.mailgun.org"
2025.08.01 12:11:04.017 *D* [ncd.smtp          ] Call to curl_easy_perform("smtp://smtp.mailgun.org:25") failed (56: response reading failed (errno: 0))
2025.08.01 12:11:04.018 *D* [nc                ] Driver error for channel "Mailgun", retrying in 30 seconds, 1 retries left
2025.08.01 12:11:34.019 *D* [ncd.smtp          ] Sending mail with url="smtp://smtp.mailgun.org:25", to="xxx@gmail.com", subject="subject4", login="xxx@sandbox8c26de1c85dc4de393a343a6f9f8f6c8.mailgun.org"
2025.08.01 12:11:35.754 *D* [ncd.smtp          ] Call to curl_easy_perform("smtp://smtp.mailgun.org:25") failed (67: Login denied)
2025.08.01 12:11:35.754 *D* [nc                ] Driver error for channel "Mailgun", message dropped

Driver configuration:
Server=smtp.mailgun.org
Port=25
LocalHostName=localhost
TLSMode=NONE
Login=xxx@sandbox8c26de1c85dc4de393a343a6f9f8f6c8.mailgun.org
FromAddr=xxx@sandbox8c26de1c85dc4de393a343a6f9f8f6c8.mailgun.org
Password=<password>
MailEncoding=utf8
IsHTML=no

]]>https://forum.netxms.org/post/34673https://forum.netxms.org/post/34673Fri, 01 Aug 2025 06:47:44 GMT<![CDATA[Reply to SMTP - Notification has been enqueued on Thu, 31 Jul 2025 10:57:29 GMT]]>Increase sever debug to level 6 (either globally or for tag ncd.smtp), then check server logs for errors. SMTP driver logs with tag "ncd.smtp".

]]>https://forum.netxms.org/post/34657https://forum.netxms.org/post/34657Thu, 31 Jul 2025 10:57:29 GMT