Most of the icons on my desktop have recently changed with a small box in the lower left corner that obliterates about 1/4 of the icon. Any suggestions as to how to get back to a full icon? Thanks.
I've had a similar problem that was caused by an overlay of shortcut arrows over my Desktop icons. If that's your problem, then this Tutorial will help: Shortcut Arrow.
If you follow the Tutorial (above) you may need to make the following adjustment: when “extracting” the ZIP file, right-click on the ZIP file, select Open With, and choose: Internet Explorer. Then select: Extract file to remove or replace shortcut arrow. That opens up a Folder, in which each of the files can be right-clicked and Properties can be accessed.
I had a similar type of problem a while back and created a thread on it, which might be of some help and guidance for your problem too:
Have you recently changed security software or backup software (especially Norton 360 but some others as well)? Some versions are known to add icon overlays to icons to indicate whether or not the file has recently been backed up. Most such software sets this by default; however, I believe most have the ability to disable this "feature" if it is not wanted. Here's an article if it is Norton 360 that is the cause: Green Tick or Blue Arrows Icon Overlay Displayed for Files in Windows Explorer - The Winhelponline Blog.