We are using the Pega OOTB activities 'SendSimpleEmail' and 'NotifyAssignee' to send outbound emails through our client's SMTP server. 
The above OOTB activities are called from our activity to send emails to different set of recipients with different templates. 
 

However on testing the emails, we found that the first few emails are delivered successfully(4 emails for example) and the next 2 sets of emails are not delivered with a time out error: "Error sending email: ** Caught com.sun.mail.util.MailConnectException, Couldn't connect to host, port: <client's domain name>, 25; timeout 60000". 
 

After this point of time, the connection to the server is cut-off. However, the connection is restored after a few minutes and the emails sent at this point of time are delivered successfully. 

What I understand is that the Pega OOTB activities 'SendSimpleEmail' and 'NotifyAssignee' do not have a queuing mechanism to put the failed emails in a queue and try again in case they face a timeout exception. Please let us know if there is a Pega OOTB feature to handle this. Will using 'CorrNew' activity help in queuing our requests? 

Do we have a retry functionality or custom code used in Pega to retry sending of the failed emails? 

***Updated by Moderator: Vidyaranjan. Removed user added Ask the Expert tag. Apologies for confusion, shouldn't have been an end-user option***