To Delete a List navigate to:
  1. Lists
  2. Click View All
  3. Search for the List
  4. Click Delete
If delete is underlined as shown below then you can Delete it from hereUser-added image

If Delete is not underlined and there is a Envelope icon next to the list
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Then you will have to remove the list from the Distribution Group it is being used in.
To see what Distribution Group the list is being used in, hover over the Envelope icon. This tells you what Group(s) this list is being used in. Once you remove the list from that Distribution Group you can delete the list.

To remove a list from a Distribution Group navigate to:
  1. onMessage
  2. Communication
  3. Pushpage
  4. Distribution Groups
  5. Click Edit on the Group you need to remove the List from
  6. Select the Remove Checkbox
  7. Click Remove Selected
  8. Click Save or Save & Exit
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