The reason for this problem is that the hidden file Shelliconcache fails to rebuild properly after changes. It is usually due to MS only setting aside 500 KB for this cache. They now suggest a maximum of 4096 KB and the easiest way to change this is to produce a .reg file.
Copy/Paste the following into NotePad, making sure you include the blank line at the end:
“Max Cached Icons”=”4096”
In NotePad, save this to any convenient folder or to the desktop, giving it the name iconfix.reg
Double click this .reg file and accept all prompts.
Reboot, because it is possible that this alone will fix the problem. If it does not then it is just a reluctance in Shelliconcache to rebuild. There is an MS procedure to prompt this but it often fails to work first time. The following works immediately:
Empty your recycle bin and delete all your desktop “shortcuts” into it. Do NOT touch any system folders such as My Computer, My Documents, Network Neighborhood, Recycle Bin, and so on. Reboot, then restore your shortcuts from the bin. The sudden changes will kick Shelliconcache into rebuilding and the registry fix will prevent or reduce the possibility of this happening again.
There is no need to retain the .reg file.