private bool HasPersonalRelationship(ADUser adUser)
        {
            if (adUser == null)
            {
                return(false);
            }
            SharingPartnerIdentityCollection sharingPartnerIdentities = adUser.SharingPartnerIdentities;

            return(sharingPartnerIdentities != null && sharingPartnerIdentities.Contains(this.callerExternalIdentity.ExternalId.ToString()));
        }
        public static bool HasSharingPartnership(Guid mailboxGuid, bool isArchive, string externalId, IRecipientSession recipientSession)
        {
            SharingPartnerIdentityCollection sharingPartnerIdentityCollection = DirectoryHelper.ReadSharingPartnerIdentities(mailboxGuid, isArchive, recipientSession);

            return(sharingPartnerIdentityCollection != null && sharingPartnerIdentityCollection.Count != 0 && sharingPartnerIdentityCollection.Contains(externalId));
        }