Official comment
We recommend creating a Campaign that Tags contacts whenever they don't open an email or click an email link over x period of time.
The Campaign instructions below addresses existing Contacts and new contacts that get created in the future who don't open an email or click an email link in 5 days time. You can easily adjust the time period to anything you'd like.
Tip: If you want to track more than just email opens and clicks, consider adjusting your Trigger to "Field is Updated" and select the Last Activity field. This field updates any time a contact performs any activity including email opens, link click, page visits, product purchased and more.
Synopsis: When a contact opens any email or clicks any link in your emails, a Tag named "Not opened in 5 days" is removed. After 5 days, if a contact does not open any email or click an email link, a Tag named "Not opened in 5 days" is added. This system works in a cyclical nature constantly waiting for opened emails or email link clicks. At any given time, you can view the contacts who are in the Tag "Not opened in 5 days" in your contacts collection or in the Campaign performance mode so you can take further communication actions if desired.
STEP-BY-STEP INSTRUCTIONS
1. Create a Campaign and add a Trigger element. Click the +Add Trigger button. Select Email is opened [Any Email]. Click the +Add Trigger button again and select Clicks an email link [0] (means any link). Adjust the Trigger settings as seen in the image below.
2. Below the Trigger element, add a Change Tags element and set it to remove the Tag "Not Opened in 5 Days". If the Tag isn't already created, you can create one by selecting + Create New Tag.
3. Below the Change Tag element, Add a Wait element. For the settings, under the Wait here until section, select Some time passes and set it for 5 days.
4. Add a Change Tags element under the Wait and add the Tag "Not Opened 5 Days".
5. Add an End element below the change tags element.
6. Locate the Added to Campaign element at the top of your Campaign. Add a Goto filter element below the Added to Campaign element and link it to the first Change Tags element which removes the Tag.
7. Add another Trigger at the top of your Campaign. Click the +Add New Trigger button and select "Contact Created". Adjust the settings as seen in the image below.
8. Add a Goto filter element below the new Trigger created in step 7, to the first Change Tags element that removes the Tag.
9. Save and Publish the Campaign.
10. To filter your existing contacts through this Campaign, navigate to your Contacts collection and select your All Group. Select All In Group and add them to the Campaign.
11. In 5 days all of your Contacts will be tracked and the Group will dynamically update as each day passes.
To view the contacts who have not opened an email or clicked a link in 5 days, view your Campaign in Performance mode. Click on the number of contacts in the Change Tags element "Add Tag: Not opened in 5 days". The Contacts collection will open and you can manually send an email broadcast or any other group action desired.