What is Microsoft SCL?

SCL — Spam Confidence Level -1 = A special value that means the message is a safe sender and is not spam. This score tells Microsoft to put the message in the inbox. 0-1 = The content of the message was scanned and determined to not be spam. These two scores also tell Microsoft to deliver the message to the inbox.

How do I set up an SCL in Office 365?

Use the EAC to create a mail flow rule that sets the SCL of a message

  1. Name: Enter a unique, descriptive name for the rule.
  2. Click More Options.
  3. Apply this rule if: Select one or more conditions to identify messages.
  4. Do the following: Select Modify the message properties > set the spam confidence level (SCL).

What is SCL in email header?

That score is mapped to an individual spam confidence level (SCL) that’s added to the message in an X-header. A higher SCL indicates a message is more likely to be spam….In this article.

SCL Definition Default action
0, 1 Spam filtering determined the message was not spam. Deliver the message to the recipients’ inbox.

What determines SCL?

Spam confidence level (SCL) When a message is inspected by EOP, the anti-spam engine will analyze the message, and will determine the SCL score for the message. According to each SCL value, there is a default action that is taken.

Why is my SCL 5?

An SCL of -1,0,1 indicates that your email is not spam and should be in inbox. An SCL of 5,6 indicates that your email is suspected to be spam. X-Microsoft Anti-Spam Header: BCL : The Bulk Complaint Level (BCL) of the message.

How can I improve my SCL score?

1 Answer

  1. Make sure that SPF and DomainKeys / DKIM are setup and working (DMARC might help you)
  2. Try disabling IPv6 when sending mail (I had the problem with postfix that the HELO headers didn’t work correctly with ipv6 and the mail got sent to spam.
  3. Make sure that your server supports TLS / SSL encryption for sending mail.

What is SCL exchange?

Spam confidence level (SCL) is a numerical value indicating the likelihood that an incoming email message is spam. SCL is a component of the Microsoft Exchange spam filter, Intelligent Message Filter (Exchange IMF).

How do I whitelist a domain in Office 365?

Office 365 Whitelist IP Address

  1. Open the Security Center (Microsoft 365 Defender)
  2. Navigate to Policies and Rules > Threat Rules.
  3. Click on Anti-Spam.
  4. Click on Connection Filter Policy (Default)
  5. Click Edit connection filter policy in the fly-out.
  6. Add the IP Address that you want to whitelist.
  7. Enable Turn on safe list.

What is SCL level?

How do I lower my SCL score?

Is there any alternatives to lower the SCL score?…Here’s what helped me:

  1. Make sure that SPF and DomainKeys / DKIM are setup and working (DMARC might help you)
  2. Try disabling IPv6 when sending mail (I had the problem with postfix that the HELO headers didn’t work correctly with ipv6 and the mail got sent to spam.

What is SCL value?

What is Exchange SCL value?