|Код NDR||Возможная причина||Решение|
|4.3.1||An out of memory error occurred. A resource problem, such as a full disk, can cause this problem.||Ensure that your Exchange server has enough disk storage. If possible, move your mail queues to an NTFS disk partition.|
|4.3.2||Available in Exchange 2000 SP1 and later. This NDR is generated when a queue has been frozen.||Unfreeze the queue.|
|4.4.1||A host is not responding. Transient network conditions can cause this error. The Exchange server automatically tries to connect to the server again and deliver the mail. If delivery fails after multiple attempts, an NDR with a permanent failure code is generated.|| |
|4.4.2||A connection dropped between the servers. Transient network conditions or unavailable servers can cause this error. The server attempts to deliver the message for a specific time period, and then generates further status reports.|| |
|4.4.6||The maximum hop count was exceeded for the message. A looping situation between the sending and receiving servers in different organizations can cause this error. The message simply bounces between the servers until the hop count is exceeded.||The maximum hop count property is set per virtual server, and you can manually override the default setting of 15. You should also check for situations that might cause looping between servers.|
|4.4.7||The message in the queue has expired. The sending server tried to relay or deliver the message, but the action was not completed before the message expiration time occurred. This message can also indicate that a message header limit has been reached on a remote server, or some other protocol timeout occurred while communicating with the remote server.||This message usually indicates an issue on the receiving server. Check the validity of the recipient address and determine if the receiving server is configured correctly to receive messages.|
You may have to reduce the number of recipients in the message header for the host about which you are receiving this error. If you resend the message, it is placed in the queue again. If the receiving server is available, the message is delivered.
|5.0.0||Note Prior to Exchange 2000 SP1, the following numerical codes all appeared under the 5.0.0. code:
Possible causes include:
- There is no route for the given address space; for example, an SMTP connector is configured, but this address does not match.
- DNS returned an authoritative host that was not found for the domain.
- The routing group does not have a connector defined; mail from one server in one routing group does not have a route to another routing group.
- An SMTP error occurred.
|On one or more SMTP connectors, add an asterisk (*) value as the SMTP address space; verify that DNS is working; ensure that routing groups have connectors connecting them. If necessary, apply the latest Exchange service pack (SP3) to isolate the issue.|
|5.1.0||This NDR is caused by a general categorizer-based failure (bad address failure). An e-mail address or another attribute could not be found in Active Directory. Contact entries without the targetAddress attribute set can cause this problem. Another possible cause could be that the categorizer is unable to determine the homeMDB attribute of a user. The homeMDB attribute corresponds to the Exchange server on which the user’s mailbox resides.|
Another common cause of this NDR is if you used Outlook to save your e-mail as a file, and then someone opened the message offline and replied to the message. The message property only preserves the legacyExchangeDN attribute when Outlook delivers the message, and therefore the lookup could fail.
|Either the recipient address is incorrectly formatted, or the categorizer was not able to resolve the recipient properly. The first step in resolving this error is to check the recipient address and resend the message.|
|5.1.1||The e-mail account does not exist in the organization where the message was sent. This can occur when users move to new locations within a site. For instance, if a former Administrative_Group_1 user moves to Administrative_Group_2, and then replies to an old mail or does not recreate an Outlook profile, an old Administrative Group style LegacyDN address will be used, and this NDR is issued. Likewise, sending mail to obsolete personal address book entries will result in this error.|
Also, if you configured your SMTP contact with invalid SMTP characters (as per RFC821), the categorizer will reject the delivery with this diagnostic code.
|Either the recipient address is formatted incorrectly, or the categorizer was not able to resolve the recipient properly. The first step in resolving this error is to check the recipient address and resend the message.|
|5.1.3||This NDR is caused by incorrect address syntax. For example, a contact that was configured in Active Directory with a targetAddress attribute but without an address would result in this error.||Either the recipient address is formatted incorrectly or the categorizer was not able to resolve the recipient properly. The first step in resolving this error is to check the recipient address and resend the message.|
|5.1.4||Two objects have the same (proxy) address, and mail is sent to that address. This issue can also occur if the recipient does not exist on the remote server.||Check the recipient address and resend the message.|
|5.1.6||Available in Exchange 2000 SP2 and later.|
One possible cause of this NDR is that the user directory attributes such as homeMDB (the user’s home mailbox store) or msExchHomeServerName (the server on which the user’s mailbox resides) is missing or corrupted.
|Check the user directory attribute’s integrity and rerun the Recipient Update Service to ensure the validity of the attributes that are required for transport.|
|5.1.7||Available in Exchange 2000 SP2 and later.|
The sender has a malformed or missing mail attribute in the directory service. The categorizer cannot deliver the mail item without a valid mail attribute.
|Check the sender directory structure and determine if the mail attribute exists.|
|5.2.1||Local mail is refused because the message is too large. A missing Master Account Security ID (SID) number on the recipient can also cause this error.||Check access permissions as well as the message size. Check if the recipient has a SID in Active Directory.|
|5.2.2||Available in Exchange 2000 SP3.|
This NDR is generated when the recipient’s mailbox exceeds its storage limit.
|Check the mailbox storage or the queue storage quota limit.|
|5.2.3||The message is too large and the local quota is exceeded. For example, a remote Exchange user might have a restriction on the maximum size of an incoming message.||Resend the message without attachments, or set the server or the client side limit to allow a larger message size limit.|
|5.3.3||When the Exchange 2000 remote server runs of disk storage to hold mail, it could respond with this NDR. This error usually occurs when the sending server is sending mail with an ESMTP BDAT command. This error also indicates a possible SMTP error.||Ensure that the remote server has enough storage to hold mail. Check the SMTP log.|
|5.3.5||A mail-looping situation is detected. This means that the server is configured to loop mail back to itself. If you have multiple SMTP virtual servers configured on your Exchange server, ensure that they are serving unique incoming ports. Also, to avoid looping between local SMTP virtual servers, ensure that the outgoing SMTP port configuration is valid.||Check the configuration of the server’s connectors for loops. If there are multiple virtual servers, ensure that none are set to “All Unassigned.”|
|5.4.0||Available on Exchange SP1 and later. Possible causes include:
- Authoritative host not found in DNS
- Smarthost entry is incorrect
- FQDN name in HOSTS file (fixed in Windows 2000 SP3)
- DNS failure occurred, or you configured an invalid IP address as your smart host
- SMTP virtual server does not have a valid FQDN or lookup of your SMTP virtual server
- A contact’s SMTP domain does not resolve to any SMTP address spaces
|Use Nslookup to check the DNS configuration. Verify that the IP address is in IPv4 literal format. Verify the valid DNS entry for the server/computer name in question. If you rely on an FQDN in a HOSTS file, ignore and update entry in Exchange System Manager with valid IP address or correct name.|
|5.4.4||Available in Exchange 2000 SP1 and later versions.|
This NDR occurs if no route exists for message delivery, or if the categorizer could not determine the next hop destination.
You set up a routing group topology, but no routing group connector exists between the routing groups.
|Add or configure your routing group connector between routing groups.|
|5.4.6||A categorizer forward loop is detected. The targetAddress attribute is set on a mailbox-enabled user.|
This common hosting configuration problem occurs when someone creates a contact in one organizational unit, and then uses the provisioning tool to create a user in another organizational unit with the same e-mail address.
|This happens when contact A has an alternate recipient that points to contact B, which then has an alternate recipient that points back to contact A. Check the contact’s alternate recipient. Check and remove targetAddress attribute from mailbox-enabled users. For hosting, where you want to send mail from one user in one company in an organizational unit to another company in a separate organizational unit, you should configure the following two related objects: User: SMTP proxy: email@example.com Contact: targetAddress: firstname.lastname@example.org; SMTP proxy: email@example.com, where contoso.com is the name of the second company.|
|5.4.8||Available in Exchange 2000 SP1 and later versions.|
This message warns of a looping condition. One possibility is that one of the recipient policies includes a local domain that matches the FQDN of an Exchange server in the organization. When the categorizer is processing mail that is destined for a domain matching an Exchange server’s FQDN, it will return this NDR.
|Check your recipient policies. If a recipient policy contains an Exchange server’s FQDN, you must remove that entry. Your recipient policy should not contain the FQDN of your server; instead, it should contain the mail domain only—for example, instead of server1.example.com, you would enter example.com.|
|5.5.0||Available in Exchange 2000 SP1 and later versions.|
A generic protocol error or an SMTP error causes this NDR. The remote SMTP server responds to a sending server’s identifying EHLO with a 500-level error. The sending system will then terminate the connection and deliver an NDR indicating that the remote SMTP server cannot handle the protocol. For example, if a Microsoft Hotmail® e-mail account is no longer active, a 550 SMTP error will occur.
|Run the SMTP Log or Netmon trace to see why the remote SMTP server rejects the protocol request.|
|5.5.2||A generic SMTP error occurs when SMTP commands are sent out of sequence. For example, a server attempts to send an AUTH (authorization) command before identifying itself with an EHLO command.|
It is possible that this error can also occur when the system disk is full.
|Run the SMTP Log or Netmon trace, and ensure there is enough disk storage and virtual memory for SMTP to operate.|
|5.5.3||Too many recipients on a message can cause this NDR.||The recipient limit is a configurable setting. To resolve this issue, either increase the recipient limit or break up the message into multiple messages to fit the server limit.|
Note The default recipient limit on an SMTP message is 5,000. To change this limit, start Exchange System Manager, expand Global Settings, right-click Message Delivery , click Properties, and then use the Defaults tab. This can also be a per-user setting in Active Directory.
|5.7.1||Possible causes include:
- General access denied, sender access denied—the sender of the message does not have the required permissions necessary to complete delivery.
- You are trying to relay your mail through another SMTP server, and the server does not permit you to relay.
- The recipient may have mailbox delivery restrictions enabled. For example, if a recipient’s mailbox delivery restriction is set to receive mail from a distribution list only, non-member’s mail will be rejected and produce this error.
|Check system privileges and attributes for the contact, and try sending the message again. Also, to resolve other potential issues, ensure that you are running Exchange 2000 SP1or later.|