Send email from Portal User (using ActivityEmailSender)

Case:

How to send email from script task from portal? I am using 

Script task code

var emailClientFactory = ClassFactory.Get<EmailClientFactory>(new ConstructorArgument("userConnection", UserConnection));
var activityEmailSender = new ActivityEmailSender(emailClientFactory, UserConnection);
activityEmailSender.Send(AddDataUserTask1.RecordId);

And i get errors on sending. I've already added Terrasoft.Core.Factories, Terrasoft.Mail.Sender, Terrasoft.Mail namespaces to my process.

Solutuion:

1. Create a shared mailbox and allow access to it for portal users

2. Open access to following objects for portal users:

• Activity
• ActivityStatus
• ActivityParticipant
• ActivityType
• ActivityCategory
• ActivityParticipantRole
• MailboxSyncSettings
• MailServerType
• MailServer
• EmailTemplate
• EmailMessageData
• EmailSendStatus
• EmailType

3. Allow access for portal users for SysSetting with code IgnoreExchangeSSLWarnings and make sure it is NOT cached