move_uploaded_file() isn't working as expected

This php function move_uploaded_file(file, destination) isn't working. The file isn't there after execution. It keeps on returning false. As it's using HTTP POST, it isn't actually getting the uploaded file to the destination folder/server in this case. After checking the errors, it says that it's error 1. But fixing it still displayed

UPLOAD_ERR_INI_SIZE Value: 1; The uploaded file exceeds the upload_max_filesize directive in php.ini.

Although other methods of file upload are described, none seems to work with the input file.