BUG: Unable to Install or Upgrade Windows Installer Service


When you install a Windows Installer (.msi) package or when you upgrade the Windows Installer engine, the installation or upgrade fails. The error messages may vary or there may be no error messages at all. The Application Event Log (which can be accessed under Administrator Tools) contains an error message entry with the source of MsiInstaller. The detail of the log reads as follows:

Exception code: C0000005 ACCESS_VIOLATION
Module: C:\WINNT\System32\SFC.DLL
Function: 0x1006ff90


This behavior occurs if the SFC.dll file exists in the System32 folder (C:\WINNT\System32\SFC.dll). The Windows Installer uses SFC.dll on Windows 2000 and, even though it is not used on Microsoft Windows NT 4, the engine attempts to load this .dll and fails.


In the System32 folder, rename the SFC.dll to another name, such as sfctemp.dll. Re-run the upgrade, or install the latest Windows Installer from the following Microsoft Web site at:

After Windows Installer is installed, rename the file back to SFC.dll.


Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

More Information

The file SFC.dll is present on the system when it is installed from third-party software.