What do you do when Explorer crashes? No matter what you do, it won't respond to mouse clicks, the windows white out and all you get is the spinning circle. Other applications are still working, it is only Windows itself that has failed. Restarting your computer is the simple answer, but what if you've got something critical running? The answer is to restart Windows without restarting your PC.
1) Save what work you can and quit what you don't need in case this trick doesn't work.
2) Invoke Task Manager by either using CTRL-ALT-DEL or right-clicking on the task bar and choosing Task Manager from the menu.
3) From the Task Manager window, click on the Processes tab and find explorer.exe (NOT iexplore.exe) in the list of processes. Highlight it and click End Process.
4) After killing the explorer.exe process, click on the Applications tab and then click on the New Task... button.
5) In the Create New Task button, type in C:\Windows\explorer.exe. Click on the browse button to make sure you're pointing to the right file. Then click Open and then OK.
Windows Explorer should now reload and give you control of your computer back. If it doesn't work, that means you probably cannot get around restarting your computer.
Even if this does regain control of your PC, reboot as soon as it is convenient as there could be underlying problems.