A deleted registry entry, a corrupt file, a bug in a recently installed program, etc. can all be causes. When it happens try using ctrl + shift + esc to launch Task Manager, then End Task the process Explorer.exe before going File->New Task and relaunching it. That should bring your desktop back, at least for the time being. My initial suggestion is to use System Restore (Windows + R and type in rstrui) to go back a day or to, before the problem began.
John
Hi. Today i had vierd thing. I just turned on computer. I play one game a bit. Then turned it off and wanted t open 1 folder. As i did everything dissapared and only wallpaper showed. I use laptop, Acer laptop. I restrted using ctr+alt+shift.. when i went back in and tryed to run Antivirus and spybot wich was in folder it happened again. I restarted and wanted to go to control panel .. and again disapared all. I used start> run for Spybot and now will see will it fix sumething. Anyone had this before?

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