Icons missing in HRPro 12?

After upgraded to HRPro 12, it is found that the small icons next to the folder items are missing.

This is the new look of HRPro version 12 that follow the design of Microsoft Outlook 2013 and most modern user interfaces. Modern user interface design preferred ca lean & clear interface and remove unnecessary distractions. 

However, to get back the icons, you can go to the top menu > Personal Options and check the Menu Tree with Icon check-box option.