Question: I'm trying to change the shortcut key for "Run Application" ( `Alt`+`F2` ) to the Windows key.

When I click "Show the panel's Run application dialog box" in Keyboard Shorcuts, it says "New Shortcut", waiting for my key combination. I press the Windows key… and nothing happens.

Answer: 
Configure postfix on the php host to act as a relay to the "good" server.

in /etc/postfix/main.cf (on the php host)

```
relayhost = goodmailserver.com

```

and do a "postfix reload"

Also ensure goodmailserver.com is configured to accept mail from your php host
I am not sure how detailed an answer you expect, but just make an SMTP connection to the machine running the email server at port 25 or whatever port it is listening on, and send an email to it to be relayed. I don't use PHP, but I expect there is some library that will do it for you. However, using your machine's email server is better.

I think this is basically the same as this question - [Send email using GMail SMTP server from PHP page](https://stackoverflow.com/questions/712392/send-email-using-gmail-smtp-server-from-php-page).