More information about Internet Explorer 8 Compatibility View

You might remember a blog we posted back in December regarding Compatibility View in IE8.  Well, we’ve come across some more interesting details and it directly effects the RC1 build.  If you’ve read the IE Dev Blog regarding Compatibility View, then you have some idea about this new feature coming with IE8.  What you may not know is that Microsoft is going to include a pre-canned list of web sites that will auto-render certain web sites in Compatibility View with no user intervention.  Keep in mind, however, that when you install the RC1 build of IE8, the Compatibility View list will be blank.  You can verify this by typing the below command into your IE8 address bar:


Typing in this command and hitting enter will prove you’ve got a blank Compatibility View list:



This is by design, as some web sites that are currently in the downloadable Compatibility View List for IE8 RC1 may make future changes to their site, thus removing the need to remain in Compatibility View mode.  This is why Microsoft feels that updating the Compatibility View List via Windows Update is the best approach and will continue to use this method when the retail version of Internet Explorer 8 releases.

To get the Compatibility View list available for IE8/RC1, just install the Updates for Internet Explorer.  You can to go to Windows Update and download a patch that will update the IE binary file containing the most current list which is iecompat.dll.  The patch number is KB961813, and it should show up under Optional Software Updates on the WU site:



Once you have installed the patch or allowed IE8 to use the Comatibility View list updates (when custom settings is chosen during the IE8 setup wizard), you can use the same command to view the currently available Compatibility View list:


NOTE:  I’ve dumped out the list of sites included in KB961813, located here.


You can disable the using the Compatibility View List by Microsoft via the IE User Interface under the IE menu under Tools –> Compatibility View Settings:


Effected registry key details:

location - HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\BrowserEmulation


REG_DWORD valeu - MSCompatibilityMode

Enabled - 1

Disabled - 0



You can also turn this off when running through the IE8 setup wizard by choosing custom settings instead of express settings :


NOTE:  The setup wizard will launch on the initial load of IE8, after installation


When you get to the Compatibility Settings dialog, choose the option to not use the Compatibility View updates:



Hopefully this blog was helpful and informative.  Look for more on IE8 in future blogs!



The IE Support Team

IE8 RC1 Compatibility View list.xls