Add below to the appropriate php.ini file (recommended if you have access). Note that for some hosts this is a system-wide parameter. However, for hosts running PHP as a CGI script using suexec (for example), you can place these directives in the php.ini file in the Drupal root directory.
upload_max_filesize = 50Mpost_max_size = 50M
Add the following .htaccess file to the Drupal root directory.
php_value upload_max_filesize 50M
php_value post_max_size 50M
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