ProFTP Unable to Upload Via Browser

If unable to upload to WordPress (eg plugins), add the following lines to the bottom of your WordPress's wp-config.php file:

 if(is_admin()) { add_filter('filesystem_method', create_function('$a', 'return "direct";' )); define( 'FS_CHMOD_DIR', 0751 ); }

to the your wp-config.php file. I had the same problem and this fixed it for me.