#M&B RECORD EXCHANGE INSTALL#

As mentioned earlier, when the recipient of an inbound message is a known recipient, the Exchange server sends back a 250 2.1.5 Recipient OK SMTP response to the sending server. Recipient Lookup functionality enables the sending server to determine whether an email address is valid or invalid. You enable the blocking of messages sent to recipients who don't exist in the Exchange organization, and the blocking of specific recipients using the Set-RecipientFilterConfig cmdlet in the Exchange Management Shell. One of the most effective ways to reduce spam is to validate recipients before accepting inbound messages from the Internet. For more information, see Enable antispam functionality on Mailbox servers.

#M&B RECORD EXCHANGE INSTALL#

The Recipient Filter agent is enabled when you install the antispam agents on a Mailbox server, but it isn't configured to block any recipients.

When recipient filtering on a Mailbox server detects one invalid or blocked recipient in a message that contains other valid recipients, the message is rejected. If the recipient isn't on the Recipient Block list and the recipient is found in Recipient Lookup, the Exchange server sends a 250 2.1.5 Recipient OK SMTP response to the sending server, and the next antispam agent in the chain processes the message.ДЄlthough the Recipient Filter agent is available on Mailbox servers, you shouldn't configure it. If the inbound message contains a recipient that doesn't match any recipients in Recipient Lookup, the Exchange server sends a 550 5.1.1 User unknown SMTP session error to the sending server. If the inbound message contains a recipient that is on the Recipient Block list, the Exchange server sends a 550 5.1.1 User unknown SMTP session error to the sending server.

These recipients are indicated by the RCPT TO header. When you enable the Recipient Filter agent, one of the following actions is taken on inbound messages according to the characteristics of the recipients. For more information, see Edge Subscriptions. On an Edge Transport server, Recipient Lookup requires access to Active Directory information that's provided by EdgeSync to the local instance of Active Directory Lightweight Directory Services (AD LDS). Recipient Lookup: Queries Active Directory to verify that the recipient exists in the organization. Recipient Block list: An administrator-defined list of recipients who should never receive messages from the Internet. The Recipient Filter agent acts on recipients from one or both of the following data sources: Mailboxes that should never receive messages from the Internet: You can prevent delivery of Internet mail to a specific mailbox or alias that's typically used inside the organization, such as Helpdesk. For example, you may want to stop delivery to frequently misused account names, such as or distribution groups: You can prevent delivery of Internet mail to distribution groups that should be used only by internal users. Nonexistent recipients: You can prevent delivery to recipients that aren't in the organization's address book. The Recipient Filter agent can help you prevent the acceptance of messages in the following scenarios: The Recipient Filter agent blocks messages according to the characteristics of the intended recipient in the organization. Recipient filtering is performed by the Recipient Filter agent, and is basically unchanged from Exchange Server 2010. Recipient filtering is an antispam feature in Exchange Server that relies on the RCPT TO SMTP header to determine what action, if any, to take on an inbound message.

M&b record exchange