ya explorer is the program that displays all the stuff on your desktop. Sometimes it crashes and restarts itself, so your desktop disappears and then reappears when explorer restarts.
A quick Google search shows that people that have recently done a virus scan and removed viruses, the process didnt fix a registry problem. Here is what another website said......
The problem you have encountered is not due to your antivirus as much as it's due to Microsoft Windows attempting to protect your computer.
Here is the scenario:
-System gets infected by a virus
-Antivirus software is installed, including updates
-Antivrus software runs, cleans out several infected files
-At next boot, Windows' shell does not run
-If you attempt to start the shell manually, you receive "Windows Cannot find explorer.exe..."
-If you look for explorer.exe in C:\WINDOWS it is present
-If you try to replace explorer.exe witha copy from a Windows CD you still get the same error.
The problem is the antivirus software has successfully removed the infection, but it has not done anything to remedy the registry entry created by the virus; it is the registry entry that is causing Windows not to run explorer.exe, and unfortunately the Windows error message is not really accurate.
In order to fix this error you must remove a key from the Windows Registry.
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Axcess Internet cannot guarantee that these problems can be solved. Modify the registry at your own risk.
1.
Open the Microsoft Windows Registry Editor by selecting "New Task" from the Task Manager (to get to the Task Manager use CTL-ALT-DEL and choose Task Manager.
2.
Scroll to HKLM (Local Machine)/Software/Microsoft/Windows NT/Current Version/Image File Execution Options/explorer.exe.
3.
In the right hand pane, find the Debugger registry key and highlight this key ONLY and delete it.
Then close the registry editor and reboot your computer. You should now see the Windows Desktop, Icons and Start Menu.
