Archiving messages in CollaborateMD is no longer supported. Only legacy customers that had archived messages prior to version 10 will have an Archive folder that will include previously archived messages. This will be a view-only folder; you won't be able to archive additional messages.
New customers or customers without previously archived messages will not see an Archive folder.
Really like archiving messages? You have the option to create your own "Archive" or equivalent folder in your account and manually filing messages there. Reference our Create a Folder Help Article for steps on how to create a new folder.