problem with helper

[eluser]_TTT_[/eluser]
On localhost I have no problems with my helper.

autoupload.php

Code:

$autoload['helper'] = array('url','form','MY_obj_helper');

application/helpers/MY_obj_helper.php

But on hosting:
An Error Was Encountered
Unable to load the requested file: helpers/my_obj_helper.php

Why ?

[eluser]_TTT_[/eluser]
$autoload['helper'] = array('url','form','obj');

same error

[eluser]InsiteFX[/eluser]
Take of the MY_

InsiteFX