The first step is to delete the documents from either the ADM launcher or the ADM client. Doing this puts the documents into the Document recycle bin.
To delete from the recycle bin:
Log into the ADM Client, under the Documents tab, select the documents.
Click Delete.
Whilst these are marked as deleted, they won't have deleted the actual files in the background and are still recoverable.
The final step is to purge the documents, this needs to be done by an administrator.
To do the final purge:
log into ADM as an Administrator.
Click System Control then click File Storage.
Click Document Recovery/Purge.
Use By Date or By User filters then click Find.
A list of all deleted documents appears, highlight all that you want to delete.
Click Purge then read the warning.
Click Yes to Purge.