I'm developing the tutorial and i've followed all steps but when I try to add a new page type i do all the tutorial says but they don't appear in the page type list. I built the datadase, I flushed and nothing. Could ypu help me please???

Couple things to check - if you installed with 2.2.3 and the tutorial theme make sure your code is in tutorial/code/ otherwise it should be in mysite/code/. Make sure your new page type has the correct code eg its at least like.

<?php 
class PageType extends Page {}
class PageType_Controller extends Page_Controller {}
?>

I must be doing something wrong. I did what you said but I still have the same problem. For example the Page Type ArticlePage doesn't appear and it's the code:

<?php

/**
* Defines the ArticlePage page type
*/
class ArticlePage extends Page {
static $db = array(
'Date' => 'Date',
'Author' => 'Text'
);
static $has_one = array(
);
static $defaults = array(
'ProvideComments' => true
);
static $icon = "mysite/images/treeicons/news";

function getCMSFields() {
$fields = parent::getCMSFields();

$fields->addFieldToTab('Root.Content.Main', new CalendarDateField('Date'), 'Content');
$fields->addFieldToTab('Root.Content.Main', new TextField('Author'), 'Content');

return $fields;
}
}

class ArticlePage_Controller extends Page_Controller {

}

?>

What's wrong with that code?????

Did you install with the tutorial option (rather then the blackcandy) and that file inside tutorial/code/

I uninstalled and installed again and I found this that could be the reason of my problems:

File permissions
Does the webserver know where files are stored? OK (C:\wamp\www\silverstripe-v2.2.3/)
mysite/ folder exists OK
sapphire/ folder exists OK
cms/ folder exists OK
jsparty/ folder exists OK

Is the .htaccess file writeable? Unable to detect whether I can write to files. Please ensure C:\wamp\www\silverstripe-v2.2.3/.htaccess is writable.
Is the mysite/ folder writeable? Unable to detect whether I can write to files. Please ensure C:\wamp\www\silverstripe-v2.2.3/mysite is writable.
Is the tutorial/ folder writeable? Unable to detect whether I can write to files. Please ensure C:\wamp\www\silverstripe-v2.2.3/tutorial is writable.
Is the assets/ folder writeable? Unable to detect whether I can write to files. Please ensure C:\wamp\www\silverstripe-v2.2.3/assets is writable.
Is the temporary folder writeable? OK

Could it be the problem?? if it's the problem, how can I fix it??

Thank you!!

thank you for all, I fixed it already!!.