Application Impersonation is a management role that enables applications to impersonate users to perform actions on their behalf using EWS. The role can be granted only to one user on the account.
Depending on the applicaiton, you may not need this role as granting Full Access to the user can be enough for the application to work. Read the Knowledge Base article How Do I Enable Send As Or Full Access Permissions On Exchange Account? for more information.
Possible scenarios for which a user may need the Application Impersonation role granted include:
- CRM integration (e.g. Connectwise)
- Integration with a telephone system (e.g. Cisco Unity Server)
- Performing scheduled local backups
To have the Application Impersonation role granted, contact Support.
Note: charges may be applied.