So, you might need to rebuild the icon cache so your icon images could be reloaded and reset.
This tutorial is done on Windows 7 operating system and it will present you two methods that you could use to rebuild your icon cache to fix the problem.
Method One: Automatically Rebuild the Icon Cache
1) Please download the file and save it onto your desktop.
2) Double click to run it.
3) Follow the instructions in the Command Prompt to rebuild the Icon Cache.
The following screen shot is for your reference.
Then press any key to exit Command Prompt.
4) Restart your computer to generate a new IconCache.db file.
Method Two: Using Task Manager
1) Right click on the empty spot of the task bar and choose Start Task Manager.
2) Under Processes tab, find the name explorer.exe, select it and choose End Process on the right corner.
Continue with the procedure by choosing End process here.
3) Go to Application bar, choose New Task… option.
4) Type in explorer.exe and press OK.
The icons on your desk top should be displayed normally now.
If you have more or better ways to deal with this issue, please feel free to leave a comment for the others to see. Thanks in advance.