setting up postfix

Hi,

When I am setting up postfix, I have typed in to putty:

sudo apt-get install postfix

then it comes up with a screen saying:

âââââââââââââââââââââââââ⤠Postfix Configuration ââââââââââââââââââââââââââ â â â Please select the mail server configuration type that best meets your â needs. â â No configuration: â Should be chosen to leave the current configuration unchanged. â Internet site: â Mail is sent and received directly using SMTP. â Internet with smarthost: â Mail is received directly using SMTP or by running a utility such â as fetchmail. Outgoing mail is sent using a smarthost. â Satellite system: â All mail is sent to another machine, called a ‘smarthost’, for â delivery. â Local only: â The only delivered mail is the mail for local users. There is no â â <Ok> â â âââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ

and nothing else, when I whatch tutorials, there is an extra bit below that says:

General type of mail configuration:

No configuration
Internet Site
Internet with smarthost
Satellite system
Local only

<Ok> <Cancel>

Why is this not working for me?

Thanks, marcus