A grey envelope signifies that a patient has provided their email address, but a copy of the patient agreement has not yet been sent.
If you wish to email a copy of the patient agreement to the patient, open the patient agreement and select "Please email a copy of my Agreement" at the bottom left corner. This will email the patient a copy of the patient agreement and will turn the envelope green.
A red envelope signifies that the patient has not provided an email address or the email address is invalid.
Therefore, you will see in the PA at the bottom left corner in red "Patient email address is invalid or missing"