I've just began learning wordpress wordpress plugin development and also got this error after i access the my wordpress plugin menu from admin.

This is actually the code: importer.php

//*************** Admin function ***************
function oscimp_admin() {
    include('importer_admin.php');
}

function oscimp_admin_actions() {
    add_options_page("OSCommerce Product Display", "OSCommerce Product Display", 1, "OSCommerce Product Display", "oscimp_admin");
}

add_action('admin_menu', 'oscimp_admin_actions');

importer_admin.php

<div class="wrap">
<?php    echo "<h2>" . __( 'OSCommerce Product Display Options', 'oscimp_trdom' ) . "</h2>"; ?>

<form name="oscimp_form" method="post" action="<?php echo str_replace( '%7E', '~', $_SERVER['REQUEST_URI']); ?>">
    <input type="hidden" name="oscimp_hidden" value="Y">
    <?php    echo "<h4>" . __( 'OSCommerce Database Settings', 'oscimp_trdom' ) . "</h4>"; ?>
    <p><?php _e("Database host: " ); ?><input type="text" name="oscimp_dbhost" value="<?php echo $dbhost; ?>" size="20"><?php _e(" ex: localhost" ); ?></p>
    <p><?php _e("Database name: " ); ?><input type="text" name="oscimp_dbname" value="<?php echo $dbname; ?>" size="20"><?php _e(" ex: oscommerce_shop" ); ?></p>
    <p><?php _e("Database user: " ); ?><input type="text" name="oscimp_dbuser" value="<?php echo $dbuser; ?>" size="20"><?php _e(" ex: root" ); ?></p>
    <p><?php _e("Database password: " ); ?><input type="text" name="oscimp_dbpwd" value="<?php echo $dbpwd; ?>" size="20"><?php _e(" ex: secretpassword" ); ?></p>
    <hr />
    <?php    echo "<h4>" . __( 'OSCommerce Store Settings', 'oscimp_trdom' ) . "</h4>"; ?>
    <p><?php _e("Store URL: " ); ?><input type="text" name="oscimp_store_url" value="<?php echo $store_url; ?>" size="20"><?php _e(" ex: http://www.yourstore.com/" ); ?></p>
    <p><?php _e("Product image folder: " ); ?><input type="text" name="oscimp_prod_img_folder" value="<?php echo $prod_img_folder; ?>" size="20"><?php _e(" ex: http://www.yourstore.com/images/" ); ?></p>


    <p class="submit">
    <input type="submit" name="Submit" value="<?php _e('Update Options', 'oscimp_trdom' ) ?>" />
    </p>
</form>
</div>

Anyone can evaluate which I'm doing wrong.

I simply attempted to alter the fourth parameter in add_options_page with basename(_FILE_) ought to be the same return with "importer.php" inside your situation. I'm not sure what it really ought to be transformed to, but it is work!

Best of luck!

Yes, Forth parameter is exclusive title, as well as for any Unique identifier it will contain space, This is the problem :)

The particular tutorial could be find HERE. Also it should use 2.9.2 version of Wordpress, a minimum of it really works for me personally. But, after i attempt to run the code from the tutorial with version 3.1 it produce exactly the same error. But as mention by Avinash the road

add_options_page(“OSCommerce Product Display”, “OSCommerce Product Display”, 1, “OSCommerce Product Display”, “oscimp_admin”);

Ought to be replace

add_options_page(“OSCommerce Product Display”, “OSCommerce Product Display”, 1, “OSCommerce_Product_Display”, “oscimp_admin”);

after which it really works correctly. Hope it will help someone.

write your importer_admin.php file code inside oscimp_admin() function or use php file_get_contents function.

The issue is 4th parameter. I've removed the spaces in the 4th parameter with _ and delay pills work.

Interesting help...