Short tag does not work...??

[eluser]Unknown[/eluser]
Hi, I am new to PHP and currently facing issues while working on my 1st PHP app.

The issue is :

<?php= form_open('expense/fix_insert');?>

would not work on my PHP view file and would not get translated to
<form method = "post" action = "http://localhost/ci/index.php/expense/fix_insert">
in the source code on the browser. I am using codeignite framework for my application and have loaded form helper in controller already.

Moreover, <?=$expenditure?> type of tag also does not work .. only when I use echo then it works..

in php.ini I have made below change:
short_open_tag = On [Portability]

please suggest.

Many Thanks,
MG