Know the answers to common questions about HES with outbound mail scanning feature is enabled.
The recommendations listed will help you understand the connection restrictions of the program when sending email via HES. These recommended actions will ensure a smooth and efficient email-based communication and that your messages will not be delayed or go undelivered.
As explained below, there are circumstances where a degree of intervention in the email delivery process is unavoidable. Also note that for privacy and fairness, we cannot prioritize handling emails of one particular sender over another.
Can we use HES outbound filtering if we are using MS Office 365 as our hosted MTA?
What setting should I use to guarantee my connection won't be blocked?
Because the load on our servers is always changing, the criteria whether a message is blocked are determined dynamically. For security reasons, we do not make these criteria public.
I need to send an important email. Can you guarantee my connection won't be blocked?
To maintain our high quality of service, there will be circumstances where we will sometimes block connections to HES.
In our role as the service provider, when service quality is impaired (due to congestion) or likely to become so, we will take appropriate measures to resolve the issue. These measures will apply regardless of the contents of the communication.
How does inbound filtering differ from connection blocking?
Inbound filtering rejects messages based on the conditions under which they were sent, with reference to predetermined criteria.
Connection blocking, on the other hand, temporarily blocks connections when circumstances, such as the load on the system, demand it. Its purpose is to ensure the stable operation of the HES system.
What is the difference between restrictions on delivering email and blocking connections?
Restrictions on delivering email means that we will reject receiving emails according to certain conditions.
Blocking connections means that we will block emails temporarily based on the system load at a particular time in order to ensure service stability.
What happens when my connection is blocked?
When your Message Transfer Agents (MTA) sends an email to HES, a 5xx error is returned in the SMTP session. This causes the MTA to send a non-delivery receipt (NDR) to the client. You can re-send the email once the MTA's connection is restored.
What are the security risks associated with forwarding email?
The concept of BYOD (Bring Your Own Device), where employees bring personal devices such as mobile phones, laptops, and smartphones to the office for work use, presents a serious IT security risk for organizations. In fact, employees will often forward their company email to mobile devices and personal addresses. Administrators should take the opportunity to review their policies in this area. Keeping the original sender on automatically forwarded emails can generate large numbers of emails to unknown recipients, which has an adverse effect on the system.
How long does email delivery in HES take?
When the HES system receives an email from a customer, it starts delivering it to its destination. Depending on the status of the destination server, HES might hold the message in the mail queue for a period of time. Because of this, an email may not arrive at its destination despite being successfully sent to HES.
- Enable spam filtering when using outbound mail scanning to prevent spam from being sent inadvertently.
- Do not send email messages with a large number of unknown recipients. These messages can cause undue burden on our servers, causing messages to become unreachable or delayed. As an anti-spam measure, we may sometimes temporary block emails of this nature.
- Do not use an excessive number of SMTP sessions when sending emails. Large numbers of simultaneous SMTP sessions can exceed the system's regular capability to process them, adversely affecting the stability of the HES system. For this reason, we will sometimes temporarily restrict the number of sessions users can establish.