Transient Suppression Lists are custom suppression lists you can add to suppress against when you send emails. 

On the navigation menu under Contacts, click on Transient Suppressions (Fig 1). 

Fig 1

Click on Upload Suppression List (Fig 2). 

Fig 2

On the Upload Suppression List window, upload your file and click on Upload & Save (Fig 3). The only file types we support are CSV and TXT. All that's required are email addresses with no other data fields. 

Fig 3

After the import is complete, you'll see the results on the Import Result window. Click OK to close the window (Fig 4). 

Fig 4

Now when you are sending an email campaign, on the final step under Advanced Settings, click the Select Lists drop-down menu to the right of Prevent sending to subscribers in list (Fig 5).

Fig 5

When you're done, click on Next and on the final Send an Email Campaign page click Schedule My Email Campaign.

If you need to delete a Transient Suppression List, navigate back to Transient Suppressions and click on the trash can icon next to the list you want to delete (Fig 6).

Fig 6

A box will pop up asking if you want to delete this list (Fig 7). Click OK to delete the list. 

Fig 7

If the deletion is successful, a pop-up window will confirm the list is deleted (Fig 8). Click OK to return to the Transient Suppression List.

Fig 8