A More Compatible IE9, Through Your Feedback

Throughout IE9, we have written about how
expect browsers to be compatible with the sites they use
every day. This blog post covers a few ways we measure and ensure compatibility
with the Web and how
your feedback
made a

Measuring compatibility with the Web

We measure Web compatibility through many different mechanisms. These include:

  • Customer feedback: Most important, we listen and act on feedback from the
    community. With 33 million downloads of IE9 Beta and RC, users logged over
    23,000 bugs
    . That’s over six times the amount of feedback we received in
    previous versions (Users logged more bugs for IE9 in part because we made it easier
    opening the Connect program to everyone
  • Professional testing: We test thousands of high traffic sites on a regular
    basis. These sites are popular with users and important to daily life around the
  • Telemetry: Across hundreds of billions of browsing sessions, we gather telemetry
    data when users click the Compat View button. We use this data to determine what
    additional sites to test and add to the
    Compatibility View (CV) List

We use all of this data, analysis, and testing to improve IE9’s compatibility with
the Web. We also use it to determine what sites are added and removed from the CV
List. For example, thanks to your feedback, we removed hundreds of sites that have
updated since Beta such as bankofamerica.com
and washingtonpost.com. This helps ensure
that all users have the best browsing experience with these sites.

New for the IE9 Compatibility View List

We made three improvements to the IE9 CV List between Beta and the final release:

  1. The IE9 CV List includes the
    software fallback list for GPU/drivers
    , which you can find at the end of
    the CV List xml file.
    This means we can update the CV List to provide users with a better browsing experience
    within days of discovering GPUs or drivers that are incompatible with IE9.
  2. The IE9 CV List includes subdomain support. This enables IE to run a specific subdomain
    in a compatible document mode, while keeping the rest of the domain running in the
    latest Standards mode.

  3. F12 Developer Tools
    tells site developers when sites are on the
    IE9 CV List
    , their
    local CV List
    , or a
    Group Policy-configured CV List
    , as shown in the screen shot

Screen shot of F12 Developer Tools showing console message that traderjoes.com is on the Internet Explorer 9 Compatibility View List

Ensure the best experience for your site

In closing, please continue to
verify your site works well with IE9
. Start by sending IE9 the
same standards-based markup
and script you send other browsers, and
feature detection
, not browser detection. Check to make sure your site is
not on the CV List.
If it is, that means customers have reported incompatibilities with your site and
IE9. To be removed from the CV List, test your site with the CV List off (Press
“F12” to bring up F12 Developer Tools and select “IE9” from the Browser Mode menu),
update your site
to be compatible with IE9. When you have verified that
your site works in IE9 Browser mode, email iepo@microsoft.com
with the information at the
bottom of this Web page
and ask for your site to be removed from the IE9
CV List.

—Marc Silbey, Program Manager, Internet Explorer

Comments (19)

  1. Anonymous says:

    Instead of reviewing telemetry from hundreds of billions of browsing sessions and maintaining an extensive compatibility view list, wouldn't it be easier just to distribute Firefox 4 with Windows? You'd get better site rendering and support for more versions of Windows.

  2. Anonymous says:

    Good one, George.  Happy April Fool's (fool).  lol

  3. Anonymous says:

    @George Smith That used to be funny some time ago. But it's not anymore..

  4. Anonymous says:

    Yes you have received thousands of quality feedback from your loyal beta testers. But most are 'Active' (Still!) 'Won't Fix' and 'By Design' If you call this ' Listening to your feedback' it's a pretty lame april fools joke.

  5. Anonymous says:

    No, it's still funny.  Mostly because it's true.

  6. Anonymous says:

    "If it is, that means customers have reported incompatibilities with your site and IE9"

    After you receive a report, do you actually check whether the site should be on the list? This seems unlikely, unless the testing is superficial, considering how big or complex some sites and apps can be.

    What if someone reports a site by mistake, or someone does so to cause problems (like someone reporting the site of a competitor just to piss them off)?

  7. Anonymous says:

    One thing I am wondering about IE9 is will it override customer error screens the way IE8 does?  What I mean is that if my site returns status 500 but sends an HTTP response with HTML, IE8 throws away the HTML and gives the user Microsoft's standard error 500 page.  The result is with my applications (Intranet I'm talking here) the user has no idea what to do to fix the problem, and they can't send me a screenshot that is at all relevant to help fix it.  I have to go to FIREFOX and reproduce the error in order to get the real error screen since IE throws away the HTML when HTTP status is not 200.  Will IE9 keep doing this????

  8. Anonymous says:

    (see above) For example, if I have a java based application that encounters an error and returns a 500 status.  The HTML returned may say "Error. The server encountered an unexpected condition which prevented it from fulfilling the request. java.lang.OutOfMemoryError    <>" which tells the user what the problem is and they can communicate to me via a screenshot or whatever what it was.  But if they go to the site through IE, they will get the worthless standard MS 500 screen and not know anything about the error being caused by java.lang.OutOfMemoryError.  This is very annoying to me.  If I wanted to hide my error messages I'd do it in the code.  I don't need Microsoft doing it for me.

  9. Mike Dimmick says:

    jun: Your custom error page needs more text. The IE friendly error page is triggered when the server sends less than 512 bytes of HTML in response.


  10. Anonymous says:

    Why not support text-shadow in IE9's CSS? It's very common these days (hell, the default ASP.Net MVC3 stylesheet uses it!) and it's supported by all other major browsers. You managed to add box-shadow support… so why not text-shadow? SOOOO Close to making IE compatible with the future direction of web design.

  11. Anonymous says:

    I am going to have to use the Mozilla Browzer has my default browzer until you fix the posting problem when using Facebook Cityville.When you post there a little thing shows on bottom of screen asking if you want to show all content ,when you see yes it refreshes the screen and you cant post again for 24 hours.

  12. Anonymous says:

    Put the search box back on the top right of IE. That was one of the best options in IE8. This searching in the address bar deal isn't working.

  13. Anonymous says:

    IE9 does not work with FB games.Does not allow you to post or give gifts.Everyone I know that has installed IE9 has had same problems and have to use Google Chrome or they have restored thier comp back to the way it was prior to this IE9 mistake.

  14. Anonymous says:

    Think its wonderful !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!  IE9 does not work with FB games.Does not allow you to post or give gifts. The best possible potential forum known to man, and they give lil gifts & UNfortunate cookies … I call them all Tard Apps … uh   DUH   wonna pla Formvil yuk yuk datz fun …

  15. Anonymous says:

    IE9 has a problem with js-sequences of document.open / document.close in a frame. After 24 open-close-loops it whitescreens without any error messages. Probably some memory issue. The XUE-header doesn't help, even without doctype the jR%^#(*^-browser still stays in IE9-mode. Why do people use this *** anyway?

  16. Anonymous says:

    I tried installing IE9 but it requires SP1 on my Vista. Tried to install update of SP1, but it always stops in the middle.

  17. Anonymous says:

    More compatible..? it took 3 years and compule of major releases. sad

  18. Anonymous says:

    IE-9's interface is ***, but they don't too much to worry about from the almost-as-buggy FF4.  FF 3.6 on the other hand…

  19. clemente Mejia Guzman says:

    Poesia ,semtimiento rap del coro cristiano apocalicse