Like how we have an option "Allow messages with unresolved email recipients to be sent" in System Settings - Set Email form options section, hopefully we can have another similar option for unresolved email senders as well. Because the Dynamics currently doesn't allow to have unresolved senders, whenever emails are received from new senders, contact records are automatically created by system - this system function cannot be disabled and it is not possible to stop it either. By having this new option, I will be able to implement a customized workflow/plugin to create a new account/contact that will have the sender's email address as the email address and manage to populate more fields on creation of this account/contact. Please consider of this idea if this can be implemented.