sendmail() gives Network is unreachable error on one of my computers

I have two PCs both with Matlab R2014a installed. The following code:

setpref('Internet','SMTP_Server','my_smtp');
setpref('Internet','E_mail','my_email@my_email.com');
sendmail({'my_email@my_email.com'},'My subject');

works on one of my PCs but on the other one it gives an error:

Error using sendmail (line 171)
Could not connect to SMTP host: my_smpt, port: 25;
Network is unreachable: connect

of couse with my real SMPT and email address inserted.

Any suggestions? The PCs are on the same network. One is 32 bit and one is 64 bit, though...

Thanks for any inputs :)

Ben

[Walter Roberson]

It could be differences in the way you set up your Windows Firewall.

[Benjamin]

Thanks for that suggestion, Walter! I tried to check and could not find any differences. Also, I added Matlab to the list "Allow programs to communicate through Windows Firewall". Unfortunately I still get the same error...

Answer 1

[Udaya Mallampati]

This error might be due to a Java Socket Exception, triggered by an interaction between Java 7 and an IPv4 connection. The Java Development Toolkit 7 (JDK) supports IPv6 on Windows machines. When you try to connect to an IPv4 address, JDK7 will use an IPv6 address that was mapped to an IPv4.

To remedy this issue, you would need to use a flag in the java run time. You can follow the below instructions for that:

• Create "java.opts" file in matlabroot\bin\arch folder.
• Write the following line in "java.opts" file:

     -Djava.net.preferIPv4Stack=true

• Restart MATLAB.

[Benjamin]

This solved the problem - thanks a million! :-)