Hidden icons in toolbar of CorelDRAW Home & Student Suite X6

Hi everyone,

I returned installation disks to FutureShop Canada 3 times because they were defective and finally bought good one from Bestbuy Canada. Installation was OK and I was enjoying program.

After I upgraded OS to Windows 10 I re-instal the program. I can use it but there is a surprise. All icons in a toolbar are invisible. The icons are there and I can see them one by one when I point a mouse in icons area. I inserted  a picture below where  you can see File icon that I pointed my mouse. My question is: How to make them visible again?

 [:(]