Outlook won't open: This functionality requires Internet Explorer 4.0 or above

Last reviewed on January 12, 2014

I'm starting to see a number of users who are having problems opening versions of Outlook that are years newer than Internet Explorer 4.

I can´t open Outlook 2010, I have Windows 7 and Internet Explorer 9. When I try to open Outlook, an error dialog says "this functionality requires Internet Explorer 4.0 or above. You can download it from Microsoft website".

When you receive this error message, it indicates the Internet Explorer version keys are corrupt.

Open the registry editor and change the values for the Internet Explorer reg key. They should be at or close to the following values if you have Windows 8 (and higher than 5).

HKEY_LOCAL_MACHINE\Software\Microsoft\Internet Explorer
Build = 98112
MkEnabled - "Yes"
Version = 9.0.8112.16421

Do It For Me

If you don't want to edit the registry yourself, you can use the following prepared registry file. To use, download it and double click to run. Note: If you use FireFox, you'll need to change the extension to reg.

For IE 8 For IE 9 For IE 10

Tip: you can open *.reg files in Notepad to view the keys and values they change.

Written by

Diane Poremsky
A Microsoft Outlook Most Valuable Professional (MVP) since 1999, Diane is the author of several books, including Outlook 2013 Absolute Beginners Book. She also created video training CDs and online training classes for Microsoft Outlook. You can find her helping people online in Outlook Forums as well as in the Microsoft Answers and TechNet forums.

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