4.3.2

Caused by administrator action using Queue Viewer.

Not applicable.

4.4.1

The host is not responding.

This error can be caused by transient network conditions. Exchange 2000 automatically tries to connect and deliver the message. If delivery still fails after multiple retries, a permanent failure NDR is generated.

4.4.2

The connection dropped between servers.

This error can be caused by transient conditions or servers that are unavailable. Exchange 2000 retries delivery for a specific time period, and then generates further reports.

4.4.6

Max hop count is exceeded for the message. This can also be caused if there is a loop situation between sending and receiving servers (the message bounces back and forth until the hop count is exceeded).

The max hop count is a per-virtual server property that can be manually overridden (the default is 15). Also check for any situations that might cause loops between servers. For more information about the max hop count setting, view the Exchange 2000 Server online help.

4.4.7

A message in the queue has expired. The sending server tried to relay or deliver the message, but the action was not completed in its message expiry timeframe.

This message usually indicates an issue on the receiving server. Verify the recipient addresses, as well as whether the receiving server is configured to receive messages correctly. Resending the message places it in the queue. If the receiving server is available, message delivery succeeds.

5.0.0

No route for the given address space (an SMTP connector is configured, but this address does not match the address space of the connector). Domain Name System (DNS) returned an authoritative host not found for the domain, and the routing group does not have a connector defined (mail from one server in one routing group has no route to another routing group).

Add an address space of type SMTP with value “*” (an asterisk) to one or more SMTP connectors.

5.1.0

General message failure that is Message Categorizer-based (bad address failure). An e-mail address could not be found.

Either the recipient address is incorrectly formatted or Message Categorizer was not able to properly resolve the recipient. Check the recipient address and resend the message.

5.1.1

The account does not exist at the organization this message was sent to.

Either the recipient address is incorrectly formatted or Message Categorizer was not able to properly resolve the recipient. Check the recipient address and resend the message.

5.1.3

Bad address syntax.

Either the recipient address is incorrectly formatted or Message Categorizer was not able to properly resolve the recipient. Check the recipient address and resend the message.

5.1.4

This error occurs when two objects have the same address as a proxy address, and mail is sent to that address.

Check the recipient address and resend the message. This can also occur if the recipient does not exist at the remote server.

5.1.6

Unknown target server. The local recipient exists in Active Directory, but Message Categorizer does not know on which server the mailbox resides.

Correct the homeMDB and msExchHomeServerName attributes for the recipients that are experiencing the issue in Active Directory. This delivery status notification code was first introduced in Exchange 2000 SP2.

5.1.7

The sender has a missing mail attribute in Active Directory. Message Categorizer cannot deliver the mail item without a valid mail attribute.

Check the sender directory structure and determine whether or not the mail attribute exists. It needs to be checked on the global catalog that the sender is looking at.

5.2.1

Message was too big.

Check the permissions as well as the message size.

5.2.3

Message was too big, local quota was exceeded (for example, the remote Exchange user may have delivery restrictions set with a maximum incoming message size).

Resend the message without attachments or set the server or client limit to allow a larger message size limit.

5.3.3

The remote Exchange 2000 server does not have enough disk storage space to hold mail.

Make sure that the remote server has enough disk storage space to hold mail.

5.3.5

Loop-back was detected (the server is configured to loop back on itself).

Check the configuration of the server’s connectors for loops.

5.4.0

A DNS failure occurred, or an invalid IP address was entered for your smart host. You also receive this error if your SMTP virtual server does not have a valid fully qualified domain name (FQDN) or lookup of your SMTP virtual server FQDN failed.

Check DNS by using nslookup dnsq. Make sure that the IP address is in IPv4 literal format. Make sure that a valid DNS entry exists for the server or machine name in question.

5.4.4

No route to message, next hop not found. You have set up a routing group topology without a routing group connector between the routing groups.

Add or configure your routing group connector between routing groups.

5.4.6

Message Categorizer forward loop detected.

This occurs if 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.

5.4.8

Warning of a looping condition.

One possible cause is that one of the recipient policies includes a local domain that matches the FQDN of an Exchange server in the organization. When Message Categorizer is processing mail that is destined for a domain that matches an Exchange Server’s FQDN, Message Categorizer returns an NDR with this error. If this message was caused by an Exchange computer's FQDN in the recipient policy, you must remove that entry.

5.5.0

General protocol error (for example, the remote SMTP server responded to EHLO with a 500 level error, and the sending system QUIT the connection. The server reported this with an NDR indicating the remote SMTP server can’t handle the protocol).

Perform an SMTP log or Netmon trace to determine why the remote SMTP server rejects the protocol requests.

5.5.2

General protocol error (for example, if SMTP protocols are out of sequence when trying AUTH before EHLO).

Make sure that there is enough disk storage and virtual memory for SMTP to operate.

5.5.3

Too many message recipients.

This is a configurable limit set on the receiving server. Increase this limit or break up the message into multiple messages to fit the server limit. Note that the default recipient limit on an SMTP message is 5000. This can be set in the Message Delivery Properties in Global Settings in Exchange System Manager.

5.7.1

General access denied error (the sender of the message does not have privileges necessary to complete delivery).

Check privileges for the sender and resend the message.

X.1.0

Other address status

X.1.1

Bad destination mailbox address

X.1.2

Bad destination system address

X.1.3

Bad destination mailbox address syntax

X.1.4

Destination mailbox address ambiguous

X.1.5

Destination mailbox address valid

X.1.6

Mailbox has moved

X.1.7

Bad sender's mailbox address syntax

X.1.8

Bad sender's system address

X.2.0

Other or undefined mailbox status

X.2.1

Mailbox disabled, not accepting messages

X.2.2

Mailbox full

X.2.3

Message length exceeds administrative limit

X.2.4

Mailing list expansion issue

X.3.0

Other or undefined mail system status

X.3.1

Mail system full

X.3.2

System not accepting network messages

X.3.3

System not capable of selected features

X.3.4

Message too big for system

X.3.5

System incorrectly configured

X.4.0

Other or undefined network or routing status

X.4.1

No answer from host

X.4.2

Bad connection

X.4.3

Routing server failure

X.4.4

Unable to route

X.4.5

Network congestion

X.4.6

Routing loop detected

X.4.7

Delivery time expired

X.5.0

Other or undefined protocol status

X.5.1

Invalid command

X.5.2

Syntax error

X.5.3

Too many recipients

X.5.4

Invalid command arguments

X.5.5

Wrong protocol version

X.6.0

Other or undefined media error

X.6.1

Media not supported

X.6.2

Conversion required and prohibited

X.6.3

Conversion required but not supported

X.6.4

Conversion with loss performed

X.6.5

Conversion failed

X.7.0

Other or undefined security status

X.7.1

Delivery not authorized, message refused

X.7.2

Mailing list expansion prohibited

X.7.3

Security conversion required but not possible

X.7.4

Security features not supported

X.7.5

Cryptographic failure

X.7.6

Cryptographic algorithm not supported

X.7.7

Message integrity failure