False Opt-Outs & Email Clicks

Two unrelated problems can skew your email reports in the same direction: automated opt-outs submitted by recipient mail servers, and clicks from anti-spam scanners that check links before delivery. Both look like real engagement in the Sent Message Report, but neither reflects a human recipient. This article explains how to spot each one and what to do about it.

False Opt-Outs

Why it happens

Most major email providers automatically click links in incoming mail to identify anything malicious. This scanning happens before the recipient ever sees the email. If the scan hits your opt-out link, or fires the List-Unsubscribe header, Act-On records an opt-out that never came from a person.

False opt-outs can be triggered by any of the following:

• HTML opt-out link.
• Text-only opt-out link.
• List-Unsubscribe header, via either forced email send or link click. Example:
  List-Unsubscribe: <mailto:unsubscribe-1234abc...@unsubscribe.b2b-mail.net>, <https://marketing.act-on.com/acton/test-list/...>
• One-click unsubscribe list header. Example:
  List-Unsubscribe-Post: List-Unsubscribe=One-Click

What you can do

Act-On cannot stop the scanning at the source, because whether an email is flagged for deeper checks is decided by the recipient's mail server. Two things you can do:

• If you can identify which opt-outs are false, remove them from the opted-out list using Managing Opted-Out or Unsubscribed Contacts in Bulk.
• If you need help identifying them, contact Support. Act-On is continuing to improve bot detection and can help review suspected false opt-outs.

False Email Clicks

What is an anti-spam appliance?

Recipient mail servers use scanners to weed out spam before it reaches the inbox. Some scanners click the first link in each message to check it for threats. Barracuda Email Security Suite (ESS) is a common example. ESS doesn't identify itself as a scanner in the way some similar products do, so Act-On can't automatically exclude those clicks.

Typical signals of scanner activity:

• A high number of clicks on a single send, often from contacts on the same email domain.
• Multiple clicks firing within seconds of the email being sent.
• All clicks hitting the same link, usually the first one in the email (often "View in Browser").
• Click patterns that are clearly not human behaviour.

Fix 1: Ignore clicks on the "View in Browser" link

We don't recommend removing the "View in Browser" link from your email header. Real recipients rely on it. Instead, use Act-On's optional setting to stop counting clicks on that link.

1. Go to Settings > Other Settings > Custom Account Settings > Labs.
2. Toggle on Ignore clicks on 'View in Browser' link.

Fix 2: Ignore known scanner IP addresses

Add the scanner's IP range to Settings > Other Settings > Internal IP Addresses. Common ranges:

Full walkthrough for adding IPs: Ignore Activity from Known IP Addresses.

Find scanner IPs from your own data (Data Studio, advanced)

If you have the Data Studio add-on, pull an Email Clickthrough report that includes the IP address field. Those are the IPs generating clicks in your emails. Confirm whether any belong to a security provider by checking their MX record:

1. Open Command Prompt or Terminal and run Nslookup (Windows guidance here).
2. Enter the IP address and the recipient's domain when prompted.
3. Look at the result. It should identify the security provider. For example, Barracuda clicks resolve to .ess.barracudanetworks.com.

Add the confirmed scanner IPs to Settings > Other Settings > Internal IP Addresses. New reports will stop counting clicks from those addresses. Existing reports are not modified.

Act-On Analytics: True Open

Act-On Analytics users can apply the True Open filter and liveboard to detect and filter suspected bot activity from email performance reports. Learn more.

Common pitfalls