Some, but not all, of my desktop icons change designs all by themselves. This seems to happen to the more recently added shortcuts (to the desktop) and almost always after my grandchildren have used the computer to visit their game sites.
These shortcut icons still open to the correct sites, so it seems not to be a hijack attempt, and the icons do return to their original design from time to time.
I am running XP Home.

Harvey

I have experienced a similar problem but it does not relate to my grandchildren. The icons change and then a few days later they reappear.

Try a program like Microsoft's TweakUI, which lets you "rebuild" the icons. The icon images are usually stored in the program's .dll or .exe file and needs to be re-associated.

Go in your Profile folder and make show you have turned on show hidden files and folders and search for IconCache.db (make a backup just in case) and delete it. It should be automatically recreated after your restart your computer and all default icons should be restored.

Good tip Ben, didn't think of that.

Another way to "rebuild" is to change the desktop color quality (i.e. from 32 bit to 16 bit).

Here is some useful info on the Icon cache Ben was referring to.

Try storing your downloaded icons on your hard drive instead of storing them on a removable media. Change your icons again using the new location to fetch from.