![Enable to send email, server reported error" or "Email server reported an error ... Could not connect to SMTP host" error when trying to send email inside 'Command Center' Enable to send email, server reported error" or "Email server reported an error ... Could not connect to SMTP host" error when trying to send email inside 'Command Center'](https://www.ibm.com/support/pages/system/files/inline-images/image_2445.png)
Enable to send email, server reported error" or "Email server reported an error ... Could not connect to SMTP host" error when trying to send email inside 'Command Center'
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Roundcube SMTP Error (-1): Connection to server failed - Articles | DirectAdmin How-to Guides and Knowledge Base
![SQL SERVER - Database Mail Error: The SMTP Server Requires a Secure Connection or the Client was not Authenticated. The Server Response Was: 5.5.1 - SQL Authority with Pinal Dave SQL SERVER - Database Mail Error: The SMTP Server Requires a Secure Connection or the Client was not Authenticated. The Server Response Was: 5.5.1 - SQL Authority with Pinal Dave](https://blog.sqlauthority.com/wp-content/uploads/2018/06/dbmail-ssl-01-800x359.jpg)
SQL SERVER - Database Mail Error: The SMTP Server Requires a Secure Connection or the Client was not Authenticated. The Server Response Was: 5.5.1 - SQL Authority with Pinal Dave
![Unable Send Email due to errors 'Cannot connect to SMTP server' or '4.4.1 Cannot Connect to Host' – KerioConnect Support Unable Send Email due to errors 'Cannot connect to SMTP server' or '4.4.1 Cannot Connect to Host' – KerioConnect Support](https://support.kerioconnect.gfi.com/hc/article_attachments/4415781987730/mceclip2.png)
Unable Send Email due to errors 'Cannot connect to SMTP server' or '4.4.1 Cannot Connect to Host' – KerioConnect Support
![e-Padi Corporation on Twitter: "Webmail roundcube mail client SMTP Error (-1): Connection to server failed https://t.co/wXN0RAK9wV https://t.co/K4dJEpRDEt" / Twitter e-Padi Corporation on Twitter: "Webmail roundcube mail client SMTP Error (-1): Connection to server failed https://t.co/wXN0RAK9wV https://t.co/K4dJEpRDEt" / Twitter](https://pbs.twimg.com/media/DPNQzy_VQAABXZu.jpg)
e-Padi Corporation on Twitter: "Webmail roundcube mail client SMTP Error (-1): Connection to server failed https://t.co/wXN0RAK9wV https://t.co/K4dJEpRDEt" / Twitter
![How to fix SMTP Error (-1): Connection to server failed in RoundCube? - Knowledgebase - AccuWebHosting How to fix SMTP Error (-1): Connection to server failed in RoundCube? - Knowledgebase - AccuWebHosting](https://manage.accuwebhosting.com/kb-images/SMTP/SMTP-1.png)
How to fix SMTP Error (-1): Connection to server failed in RoundCube? - Knowledgebase - AccuWebHosting
![SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting - Software Support - PKP Community Forum SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting - Software Support - PKP Community Forum](https://forum.pkp.sfu.ca/uploads/default/original/3X/4/e/4ed7bdd8c1f818c65de48fe82a3260cfcb47a6b7.jpeg)
SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting - Software Support - PKP Community Forum
![How to fix SMTP Error (-1): Connection to server failed in RoundCube? - Knowledgebase - AccuWebHosting How to fix SMTP Error (-1): Connection to server failed in RoundCube? - Knowledgebase - AccuWebHosting](https://manage.accuwebhosting.com/kb-images/SMTP/SMTP-4.png)