[eluser]Mowgli[/eluser]
Ok, i did some debugging and i realized i was passing the config variables while loading the library so i had to add a new line of code, for initializing.
$this->load->library('upload', $config);
$this->upload->initialize($config); //new line
All .doc files i tested seem to work fine. On the other hand though PDFs won't work at all and i don't get any error which is weird. Same goes for huge size .rar files (i disabled max_size). Small ones work just fine. Maybe there's a problem with the mimes ?