Blank desktop or illegal operations error message after you install Internet Explorer

The Microsoft Windows Explorer shell may not load (leaving you with a blank desktop), or you may receive the following error message when you restart your computer after you install Internet Explorer 5.0 or later: When you click Details, you receive the following message, where filename is either the Explorer.exe or Shdocvw.dll file:

This behavior can occur if any of the following conditions are true:

• The Shdocvw.dll file is missing or damaged.
• The Windows 98 Registry Checker (Scanreg.exe) restores a previous copy of the registry. To determine if this has occurred, check for a Rbbad.cab file on your computer with the same date stamp as the day that you installed Internet Explorer 5 or later. If the file is on your computer, follow only steps 8 through 10 in the "Workaround" section of this article.
• The computer is infected by the Pretty Park virus.

NOTE: If you believe that the Pretty Park virus or any other virus infects your computer, do not use the following steps. Instead, obtain an up-to-date version of an antivirus utility and scan your computer with the program.

For additional information about the Pretty Park virus, click the following article number to view the article in the Microsoft Knowledge Base: If you are certain that your computer does not have a virus, use the following steps to work around the problem:

1. Start your computer from a command prompt, edit the System.ini file by changing Shell=Explorer.exe to Shell=Winfile.exe, and then restart your computer. You can perform the preceding step by following these detailed instructions:
   1. Restart your computer, and then press F8 when you see the "Starting Windows" message.
   2. Use the ARROW keys to highlight Command Prompt Only, and then press ENTER.
   3. To edit your System.ini file you may first need to change directories to the Windows directory by typing cd\windows, and then press ENTER.
   4. To edit your System.ini file, type edit system.ini, and then press ENTER.
   5. At this point you should see text from the System.ini file. Look for a line of text that says:
      Shell=Explorer.exe
   6. Delete the Explorer.exe text and replace it with:
      Winfile.exe
   7. To save your changes, press ALT+F.
   8. A menu is displayed in the upper left corner of the screen. Press the X key to exit.
   9. Press ENTER to save changes and to return to the command prompt.
   10. Restart your computer normally. You should see the Windows File Manager once Windows has restarted.
2. Click Run on the File menu in File Manager, type command.com, and then click OK.
3. Re-extract the Shdocvw.dll, Mshtml.dll, Comctl32.dll, and Shlwapi.dll files from the Internet Explorer 5 cabinet (.cab) files.
   
   For information about how to extract Internet Explorer 5.0 files, view the "Extracting Individual Internet Explorer 4 or 5 Files" section of the following article in the Microsoft Knowledge Base:
   129605 How to Extract Original Compressed Windows Files
4. Edit the System.ini file by changing Shell=Winfile.exe to Shell=Explorer.exe, and then restart your computer.
   
   If the issue is not resolved, continue with the next step.
5. Start your computer from a command prompt, edit the System.ini file by changing Shell=Explorer.exe to Shell=Winfile.exe, and then restart your computer.
6. Click Run on the File menu in File Manager, and then type the following command:
   rundll32 setupwbv.dll,IE5Maintenance "C:\Program Files\Internet Explorer\Setup\SETUP.EXE" /g "C:\WINDOWS\IE Uninstall Log.Txt"
   This command runs Internet Explorer Repair (if available) and is case sensitive. If you are prompted to restart Windows to complete the repair process, click No, and then continue with the next step. If you are prompted to run Setup again to reinstall all components, click Details to note the problem, click OK twice, and then continue with step 9.
7. Edit the System.ini file by changing Shell=Winfile.exe to Shell=Explorer.exe, and then restart your computer.
   
   If the issue is still not resolved, continue with the next step.
8. Start your computer to a command prompt, edit the System.ini file by changing Shell=Explorer.exe to Shell=Winfile.exe, and then restart your computer.
9. Click Run on the File menu in File Manager, and then double-click the Setup.exe file in the Program Files\Internet Explorer\Setup folder (where Internet Explorer is the name of your Internet Explorer installation folder).
10. Click OK, and then click Yes to remove Internet Explorer.
11. Click Restart Windows, restart to a command prompt, edit the System.ini file by changing Shell=Winfile.exe to Shell=Explorer.exe, and then restart your computer.
    
    If the issue is resolved, run an antivirus program with updated signature files, perform a clean start (disable any antivirus or "crash"-protection software), and then start Internet Explorer.