There are a few simple reasons why you may not send emails.
Are your email settings correct?
Make sure the email account username and password you enter in your email client are correct.
The details you'll need to be using are found below:
Account type: IMAP
Incoming mail server: imap.yourdomain.com
Outgoing mail server: smtp.yourdomain.com
Incoming server port (IMAP): 993
Use the following type of encrypted connection: SSL
Outgoing server port (SMTP): 465 (or 587)
Use the following type of encrypted connection: TLS
Are email sending limits being hit?
Our mail platform has several limits to protect the reputation of the mail platform and prevent large quantities of spam emails being sent. Currently, our mail limits are as follows:
Web servers: 500 emails a day.
Mailboxes: 8000 emails a day.
Message size/attachments: our webmail system accepts attachments up to 32MB in size, and the maximum message size in our network is 50MB.
If any of these limits are breached, it won't be possible to send mail from that hosting package or mailbox. In the case of the message size/attachment limit, you'll simply need to look at reducing the size of the email or attachment being sent.
Where do the MX records point?
You can easily ensure controlpanel.Systems serves the emails by using the tool here: https://mxtoolbox.com/
If we host the emails then you'll see mx.stackmail.com returned. If anything else is returned, you may wish to contact the provider to determine the cause of the issue.
Is the mailbox disabled for suspicious activity?
If you're receiving the following error when seeking to send, the mailbox may have been disabled for sending suspicious emails.
"SMTP: Error (550): Failed to add recipient “test@example.com” (Sending mail from this address has been disabled due to suspicious activity)."
If you've received this error, please contact our Support Team, they can get this resolved for you.