Small folder images on icons

[crl123]

Hello, I am new and hope I posted this in the right category, I simply don't know where to put this.

Today some of the files on my laptop had new icons. This only happened to powerpoint and Adobe Reader documents.The icons used to be previews of the first page of the docuent for the poweroint files, but now they have small images of a folder in the lower right corner.

Could anyone tell me why this happened and how I can remove them?

 

[GokAy]

There is http://www.sevenforums.com/tutorials/49819-icon-cache-rebuild.html

but

This will not help with any of the following icon issues:
All icons for a specific file extension display the wrong icon. This may be due to setting the wrong association for what program to open the file extension instead. You can restore the default file extension's associations to fix this icon instead.

Perhaps a System Restore prior date before the issue existed will help if above fail. http://www.sevenforums.com/tutorials/700-system-restore.html

Also found:
Open the folder where you have all the PowerPoint files click on Organize button on the Top left hand corner below the address bar > Click Folder and search options>Click on the view tab>uncheck the option "Always show icons never thumbnails" >click apply and click ok.