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Installation Error 0x80070643

Hazr asked on

Issue: You are receiving an error 0x80070643 when installing Microsoft Security Essentials.

See possible workarounds below:

Please refer to this content “I cannot install Microsoft Security Essentials” to address the following solutions:

1.      Remove any existing Internet security programs (antivirus/antispyware software).

·     Uninstall other antivirus/antispyware software on the machine prior to installing Microsoft Security Essentials

·     Antivirus/antispyware software may not uninstall completely and it would require running the appropriate cleanup tool to do a clean uninstall.  These tools are typically found within the product sites.  After completing a clean uninstall using the clean up tools, reboot the PC machine, and then install Microsoft Security Essentials.

2.      Make sure that the Windows Installer service is running

3.      Start Windows in Selective Startup mode


If you recently uninstalled OneCare, follow the steps below:

1.      Download the OneCare Utility clean up tool Copy the following web address, open your Internet browser, paste the address in the address box of your browser, and then press ENTER.

2.      Click Save.

3.      Select a location where you want to save the file, and then click Save.

4.      Go to the location where you saved the file.
In Windows XP, double-click the file.–or– In Windows Vista, right-click the file, and then click Run as administrator.

5.      Click Run, and then click Continue.

6.      Read the licensing agreement. If you agree to it, click I accept the terms of the End?User Licensing Agreement, and then click Continue.

7.      Click Clean.

8.      After the clean-up tool finishes, click Restart Now.

9.      After booting up the PC machine, install Microsoft Security Essentials


If the failure is on XP machine, check if the machine has windows installer 3.1 or above.

1.      We have a dependency and the AM bits install only if the XP machine had windows installer 3.1 or above

2.      Windows installer 3.1 can be manually installed from - http://support.microsoft.com/kb/893803

If the workarounds above do not resolve your issue, check the install logs:

1.      Find the install logs from this path:
(XP) - \Documents and Settings\All Users\Application Data\Microsoft\Microsoft Security Essentials\Support\msseInstall.log 

(Vista/W7) - \ProgramData\Microsoft\Microsoft Security Essentials\Support\msseInstall.log

2.      Open the log and search for "return value 3" and you will see the error just above the first result.  See sample logs below. If you see the same items within the log, continue to the next step.

      MSI (s) (CC:2C) [13:27:24:987]: Hello, I'm your 32bit Elevated custom action server.

      MSI (s) (CC:E0) [13:27:25:283]: User policy value 'DisableRollback' is 0

      MSI (s) (CC:E0) [13:27:25:283]: Machine policy value 'DisableRollback' is 0

      Action ended 13:27:25: InstallFinalize. Return value 3.

 3.      Click Start then click Run

4.      Give everyone permission to the desktop by typing the following command:

·         CACLS “c:\documents and settings\all users\desktop” /t /g everyone:f

5.      Give everyone permission to the Program menu by typing the following command:

·         Vista/Win7: CACLS “C:\ProgramData\Microsoft\Windows\Start Menu\Programs” /t /g everyone:f

·         XP: CACLS “C:\Documents and Settings\All Users\Start Menu\Programs” /t /g everyone:f



Visit the Microsoft Virus Solution and Security Center for resources and tools to keep your PC safe and healthy.  If you are having issues with installing the update itself, visit Support for Microsoft Update for resources and tools to keep your PC updated with the latest updates. 



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