Add Media button missing on posting form

I found the answer a while ago:

Fix is to add this at end of theme’s functions.php:

if ( current_user_can('contributor') && !current_user_can('upload_files') )

	add_action('admin_init', 'allow_contributor_uploads');

function allow_contributor_uploads() {

	$contributor = get_role('contributor');

	$contributor->add_cap('upload_files');

}

thank u for ur ans.
i found that also before.
but without this code also upto contributor can see add media button (only subscribers cant see).

but they can see all media. i tried many code to restrict them to see only their media but nothing is working for me.

i got the perfect code to show only his/her media.
but contributor cant upload media. give error “An error occurred in the upload. Please try again later.”

I’m having this exact problem, but nothing is working — not even the code in this thread.

Any other ideas on how to fix this??