Question

I am trying to activate a tiny plugin on WordPress that is running on localhost but it runs into the following error:

The plugin generated 6 characters of unexpected output during activation. If you notice “headers
already sent” messages, problems with syndication feeds or other issues, try deactivating or
removing this plugin.

<?php
/*
Plugin Name: myphoto Plugin
Description: A plugin to retrieve photos and share them on the wordpress.
Version: 1.0
Author: Saeed pirdost
Copyright: 2012,  Saeed pirdost  
*/
?>
<?php
myprint();
function myprint()
{
    echo "hello";
}
?>

Answer 1

Try remove some things and use a suitable hook.

<?php // remove all spaces up of here too
/*
  Plugin Name: RePhotosPic Plugin
  Description: A plugin to retrieve photos and share them on the wordpress.
  Version: 1.0
  Author: Saeed pirdost
  Copyright: 2012,  Saeed pirdost
 */

// remove     ?> <?php

add_filter('admin_notices', 'hello');

function hello()
{
    echo 'Hello';
}

// remove ?>

UPDATE:

Remove myprint(); place it inside a WP hook too. Like this:

add_filter('admin_notices', 'myprint');

function myprint()
{
    echo "hello";
}