When trying to send emails to the members of a large SharePoint group, the workflow instance sends duplicate emails.
ERROR CODE
RESOLUTION
Option 1
Assign the email action to an Active Directory Mail-Enabled Security Group, to have the email action processed by Exchange instead of SharePoint.
Option 2
Add a one minute pause at the start of the workflow design. This gives the workflow engine enough time to instantiate the group members initially, resultingĀ in just one email being sent.