A message might be blocked if it contains suspicious-looking or spammy text, or if the sending user has had a history of sending unsolicited messages.
What can I do?
If your account is sending spam, chances are it has been compromised in some way. Change your email and control panel passwords, and make sure you use a password that has
- At least 10 characters; and,
- A mixture of upper and lowercase letters, numbers, and symbols ($#%, etc.).
Once you have changed your password, run a virus scan to make sure your computer has not been compromised by spam-sending software (Virus/Trojan)
Once the situation is resolved the block should removed automatically after a short period of time. If you are still receiving an error please contact us with the most recent error so we can investigate further:
Content retrieved from: https://support.appliedi.net/kb/a946/mailchannels-error-550-5_7_1-our-system-has-detected-that-this-message-is-likely-unsolicited-mail.aspx.