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MFC42.DLL | Windows98 |

Note: New MFC42.dll problem as of January 12, 2003, that prevents Explorer/Outlook/Control Panel and other programs from opening.

This is a common problem with windows. In most cases, the correct version of this file was overwritten by another version with the same name causing the problem.

Also see the MFC42.DLL Errors page.


When you find this file, it will probably be in more then one folder and is most likely the cause of the problem. The version located in the c:\windows\system folder should be the same as any other version found.. 

Note : if during the search you find a copy in a folder called CABS leave it alone.

Most of the time if you run the SFC utility and have it replace the copy in the system folder the problem will go away. Unfortunately, many programs load their own copy in their own folder causing the problem. In this case you have several choices. 

Rename any MFC42.dll files you find other then in the \system and \CABS folders from MFC42.dll to MFC42.OLD, and reboot the computer. This can only be done from a true DOS prompt and not from within Windows. 

This file cannot be renamed or removed from inside Windows.
  • Restart the computer in MS-DOS mode
    click the Start button, click Shut Down, In the Shut Down Windows dialog box, click Restart the computer in MS-DOS mode, and then click OK.
  • At the command prompt, type: CD\System Press the <ENTER> key
  • At the C:\Windows\System prompt, type: Ren mfc42.dll mfc42.old. Press <ENTER>
  • Assuming you have a good copy of MFC42.DLL on the root of the C drive do the following...
    At the command prompt, type: 
      Copy c:\mfc42.dll c:\windows\system\mfc42.dll
    Press ENTER. The Mfc42.dll file will be copied to the hard drive
  • Turn off the computer and after a few seconds back on. The MFD42.DLL file should now be updated.


If there is a problem you can always change the name back to the original. Do this one file at a time. If you find 3 MFC42.dll files then rename the first, reboot and try it, if you still have the problem rename the next and so on. Eventually you should end up with only one copy of this file in the system folder (and maybe one in the CABS folder).

If this does not fix the problem then you can rename the MFC42.dll file found in the system folder to MFC42.OLD, then one file at a time, copy one of the other MFC42.dll files you found in the other folders to the c:\windows\system folder and rename it to MFC42.dll .What you are trying to do here is to use the other versions and see if they work better. 

In almost all case one of the above will fix the problem.


Download MFC42.dll -




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