Your php doesn't include the EXIF support.

Solution 1

Ask your provider to add in their php.ini
extension=php_exif.dll


Solution 2 (They don't want)

You will run without the EXIF support.
Install plugin [extension by Piwigo Team] LocalFiles Editor
Active it.
In its first tab (Configuration) just add:

$conf['show_exif'] = false;