Error Message about Sunrise.php file

Please how can I solve the problem below.
I received the message when I was trying to carry out the instruction given in Domain Mapping settings of my network.
I followed the instructions of moving sunrise.php from my plugin folder to my wp-content folder, but received this message that says I am using an old version of sunrise.php. Please help.

"You are using an old version of /home/royo2688/public_html/wp-content/sunrise.php file. Please, replace that file with a new version which is located by following path: /home/royo2688/public_html/wp-content/plugins/domain-mapping/sunrise.php."