Why then are some of our standard users not able to address a comment to some individuals and not others? For example they can address a comment to a power user but not to another standard user. All of the users have permission to the same folder. Thanks Stacey
Since Standard User accounts are for external collaborators, they can only "@mention" other Power Users with access to the folder to avoid exposing 3rd-party data (i.e., another Standard User's name and email address).