I am running sbs2003 with exchange 2003 sp2 on it...i am constantly getting these errors in the event viewer. Any help cleaning these up would by very nice Event Type:WarningEvent Source:MSExchangeTransportEvent Category:SMTP Protocol Event ID:7002Date:9/13/2007Time:10:10:38 AMUser:N/AComputer:PSC-S1Description:This is an SMTP protocol warning log for virtual server ID 1, connection #40. The remote host "24.248.93.51", responded to the SMTP command "rcpt" with "452 4.2.2 Disk quota exceeded ". The full command sent was "RCPT TO:<xxxx@xxx.com> ". This may cause the connection to fail. For more information, click http://www.microsoft.com/contentredirect.asp. Event Type:ErrorEvent Source:MSExchangeTransportEvent Category:SMTP Protocol Event ID:7004Date:9/13/2007Time:9:52:30 AMUser:N/AComputer:PSC-S1Description:This is an SMTP protocol error log for virtual server ID 1, connection #38. The remote host "216.173.246.161", responded to the SMTP command "mail" with "530 authentication required for relay (#5.7.1) ". The full command sent was "MAIL FROM:xx@xxx.xxx ". This will probably cause the connection to fail. For more information, click http://www.microsoft.com/contentredirect.asp. Event Type:ErrorEvent Source:MSExchangeTransportEvent Category:SMTP Protocol Event ID:7004Date:9/13/2007Time:9:41:14 AMUser:N/AComputer:PSC-S1Description:This is an SMTP protocol error log for virtual server ID 1, connection #37. The remote host "209.106.229.5", responded to the SMTP command "xexch50" with "504 Need to authenticate first ". The full command sent was "XEXCH50 2332 2 ". This will probably cause the connection to fail. For more information, click http://www.microsoft.com/contentredirect.asp.

Here, check this link out to troubleshoot Exchange Transport problems. http://support.microsoft.com/default.aspx?scid=kb;en-us;821910From a newsgroup post: "This is an alert that a host has tried to pass an XEXCH50 command without passing authentication credentials first. The XEXCH50 command is normally only issued between Exchange servers in the same organization. If this is coming from an outside host, someone may be trying to implement a denial of service attack against your server. If you have not already installed the September post-SP3 rollup package for Exchange 2000, you may want to consider doing so".From a newsgroup post: "If the only problem you are seeing is that XEXCH50 is being denied in some cases, but there is no mail flow problem, it sounds like everything is ok as long as XEXCH50 is only being denied from servers outside of your Exchange Organization and mail is still being received.Exchange 2003 only accepts XEXCH50 protocol data from clients who authenticate and have been granted "Send As" permission on the receiving SMTP virtual server object in the AD. In this respect, Exchange 2003 behaves differently than Exchange 2000. Within a single Exchange organization, Exchange setup takes care of ensuring that all Exchange servers have the necessary "Send As" right on all of the SMTP virtual servers, through the ACL on the Exchange organization object in the AD which inherits down to all of the SMTP virtual server objects. Because of this, the XEXCH50 command should be properly sent and received between servers within a single Exchange organization. It is expected that Exchange 2003 will block inbound XEXCH50 data from other Exchange organizations by default, and in this regard, the fact that it is responding with "504 Need to authenticate first" is actually correct, if the remote server is not part of the same Exchange organization. If you are seeing this between servers in the same Exchange organization, that is potentially an authentication or ACLing problem that should be looked into. You can use ADSIEdit.msc to investigate the ACLs of the Exchange objects in the configuration container if you suspect that the necessary Exchange server security groups have not been granted the Send As access that they need on the SMTP virtual servers. If you are seeing this between servers in different Exchange organizations, it is normal expected behavior, and should not actually block mail flow. When Exchange 2003 rejects an inbound XEXCH50 attempt, it allows the client to continue without the XEXCH50 data. When Exchange 2000 or 2003 attempt to send an XEXCH50 command and are denied, they continue to try to send their message data". here is a link for the 7002 event IDhttp://www.microsoft.com/technet/support/ee/transform.aspx?ProdName=Exchange&ProdVer=6.5.6940.0&EvtID=7002&EvtSrc=MSExchangeTransport&LCID=1033