Admins may use the 'set access' function to restrict access to a certain file or files. First select the file(s) you wish to restrict (click on individual files to select them one at a time or use click and shift to select multiple files), then choose the 'set access' option in the drop down list that appears under 'actions'.
A pop up box like this will appear:
You can then choose if you wish to limit access to the selected file(s) to users who have permissions for either 'internal' or 'confidential' files. This means that only registered users with corresponding access permissions will be able to view or view/download (depending on permissions granted) the file(s) for which access has been set.
Only admins are able to grant access permission in the in the 'User Info' page, which can be accessed by clicking on a user's name in the user management area.
Please note that by default we offer two levels of access - 'internal' and 'confidential' - but these can be renamed and you can add additional filters if you wish.