Check if your mail server is relaying messages

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It’s a bad thing if you have an open mail server which relays messages for unauthorised people.

Here is a quick guide on how to check it. Log on to your server and go to a command promt or the CLI

telnet relay-test.mail-abuse.org

If it’s connected it will look like this:
RJT002:/var/log# telnet relay-test.mail-abuse.org
Trying 168.61.4.13...
Connected to cygnus.mail-abuse.org.
Escape character is '^]'.
Connecting to 85.17.173.71 ...
<<< 220 myupload.dk ESMTP Postfix (Debian/GNU)
>>> HELO cygnus.mail-abuse.org
<<< 250 myupload.dk

It will now make some test to check if your system is open or not:

:Relay test: #Test 1
>>> mail from:
<<< 250 2.1.0 Ok
>>> rcpt to:
<<< 554 5.7.1 : Relay access denied
>>> rset
<<< 250 2.0.0 Ok

After testing you get the result. If it's look like this, then you're secure:

Tested host banner: 220 myupload.dk ESMTP Postfix (Debian/GNU)
System appeared to reject relay attempts

Enjoy.

Low hanging fruits – Windows – Episode 1

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In my work I often have to give people a new password, because they forget it after every holiday. They call me on the phone, so i can’t see their screen.

Here is what people are seeing:

They call me and tell me that they need a new password. I reset it to a standard password and set it to expire, so that they must change it at first logon.

Here is what Microsoft really needs to change. When people start pressing their password wrong multiple times, they do not read the text, but only look for the X symbol:

At this point, everyone has associated that symbol with “WRONG PASSWORD”.

Here is what they see when they are asked to change the password, after they have typed in the password I have given them. (The picture is from a server 2008 logon screen, but they same message appears in Windows 7 and Vista):

Here the symbol is again, and people think that i have given them a wrong password. And that leads to a lot of confusion, because I cant see their screen.

It would be easy for Microsoft to add an “attention triangle” instead of the X, and it would save so many confusions.

I hope it will be changed in Windows 8. Microsoft, please do!