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Email Originator <>

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by admin

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We have a MS Exchange 5.5 server running on Win NT4. Problem I've encountered is something is sending emails through our server to verious domains with the originator as <>. Eventually the message will time out and send me a mail failure notice. When I go into Exchange Admin and look at the message in our IMS Queue, it states the host is unreachable. The address will have our domain with one of our users address, but will be trying to send the message to other various domains. Originator alwaysshows up as <> with nothing between the signs. The log files don't ever show these messages, but if I pick one of our users names that is listed in the message in the IMS queue I have found some strange email addresses. The email address is a stringof #'s and alpha characters seperated by periods @aol.com. I have submitted test for an open relay to ordb.org multiple times and they come back with us having no open relays. HELP!

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by lordinfidel

Congratulations, You have sucessfully configured your exchnage server to not relay.

Here is what is happening.

Spammer A " methrowspam@u.com " tries to relay thru your mail server.

Your mail server says "Hey YOU BAD MAN, YOU NO RELAY"

Itthen sends a NDR back to methrowspam@u.com . So if you look on the left side of the que. You will see lot's of thes to the u.com domain coming from <>.

Now who the hell is <>? you ask.

<> is your mail server.

You will eventually get a NDR delivered back to you your mail box saying methrowspam@u.com is an invalid host or mailbox limit exceeded.

To stop this notification, simply turn off the notifications in exch admin/connections/IMS/set mailbox- notifications. to only outbound failures.

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