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Can't Block an IP Range from Connecting to My Server!

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life036

IS-IT--Management
Mar 29, 2005
25
US
Hello Friends,

I was wondering if anyone could tell me what I'm doing wrong here... I just set up exchange a couple of weeks ago, and am still confused about the settings which never seem to work logically the way they're supposed to (well, according to my logic at least).

Basically, I want to stop these bastards at hinet.net from sending mail through my server. Here's a picture of the queue. This means that they're using my server to relay, does it not?:
queue.jpg


Here's some of the addresses that are in the queues:
senders.jpg


Judging from the domains, it looks like the messages are using Chinese or Korean encoding. Does this mean that my relay is open, plus somebody jacked my postmaster account? I've already tried changing the Administrator password. I even deleted the postmaster email address from the Administrator account, and still get the same thing...

I've set up a sniffer on the inside of our network, and none of these messages are originating internally.

So I tried blocking the IP address range of those domains (168.95.4.1 - 168.95.4.254) using the global deny list, which doesn't seem to work. Are my settings incorrect?:
deny_list.jpg


I also tried to change the access settings in the smtp virtual server as such, with no luck:
authentication.jpg


connection.jpg


relay_restrictions.jpg


Can anyone tell me what I'm doing wrong? I can't prevent this darn IP range from using my server!

I WOULD try unchecking anonymous access, but whenever I do that nobody can send anything at all to my users from the outside!!!

Thanks for your help,
Chris
 
I'd look there
and your relay settings are wrong. You should not allow everyone BUT list below. You should only allow a given list (pretty, if you have only one exchange box, you should not allow anyone at all to relay through you).

Your last box says "I'm open relay except from hinet.net".. not too good :)

Chris
 
You don't want to untick anonymous or you won't receive email from outside - that's by design.

Does external email come straight to Exchange or is there another endpoint?

I agree with Chris about the relay - change it to only allow and unless there is a reason, the box below that should be blank and the tick box should be unticked.
 
And recreate the postmaster account. It's required by RFC.

Pat Richard, MCSE MCSA:Messaging CNA
Microsoft Exchange MVP
 
Hi Guys, thanks for the input! I was able to fix the problem with your suggestions, and tightened up the security a bunch.

I also recreated that postmaster account, and everything is looking good!

Thanks,
Chris
 
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