Win7 system mistakenly delete QQ friends how to do?

What should I do if the win7 system accidentally deletes QQ friends?

1. After logging in to the QQ account first, we click on the inverted triangle next to the QQ name on the main panel, and then click on “My QQ Center” function key;

2 Pop-up "My QQ Center" page, on this page we click on the "Data" button in the top toolbar;

3, come to the "data" page, at the most At the bottom of the toolbar above, the green function key of “Retrieve lost friends” will appear. We click on the function key;

4. At this time, the page will go to the “QQ Recovery System” page, then we Click “Restore QQ Friends" function button;