IE8 in Windows 7 RC: Reliability and Telemetry

With the “final” release of IE8 for Windows Vista and other versions of Windows in several languages, we’ve been focused on finishing IE8 in Windows 7. We’ll blog soon about the updates in IE8 in the Windows 7 Release Candidate around the Windows 7-specific features, like tabs in the taskbar, jump list, and touch. Today’s post is about reliability and telemetry.

As in Win7, an important goal in IE8 was increasing reliability. For example, IE8 isolates crashing tabs from each other. If you’re listening to music in one tab, and the site you’re using in another tab crashes, IE8 isolates the crashed tab so the music doesn’t stop playing. We also pay very close attention to the data that users opt-in to sending Microsoft about their experience. We use that telemetry to adjust the product after release. We described some examples in another post during the Windows 7 Beta.

Delayed responsiveness (or a “hang”) or non-responsiveness (or a “hard hang”) are just as frustrating to users. For the Win7 RC, we wanted to get much, much better telemetry about browser responsiveness “in the real world.” There’s a challenge in having software detect non-responsiveness in itself, kind of like asking a classroom “anyone not here please speak up.” 

For the Win7 RC, we added functionality to IE8 that lowers the threshold for identifying delayed responsiveness that might be a hang. Basically, IE’s frame uses a timer, and if the tab doesn’t respond within a given interval of time, the frame gives the user the choice to recover the page, close the page, or wait for the tab to respond. If the tab responds on its own, IE takes down these choices. 

Webpage Not Responding Diaglog in IE8

A tab might become non-responsive like this for different reasons. The webpage in the tab might use a plug-in that is very busy pulling down a lot of video information from a slow server and then processing it. The webpage might be on an intranet (e.g. http://salarydata) and different authentication mechanisms are negotiating, slowly, what the user is allowed to see. Sometimes, it’s an issue with IE. Better telemetry here is crucial in figuring out what we, as engineers, do differently here.

Whatever the underlying reason, the challenge here is how sensitive to make this timer.  Too long a timer (for example, 10 minutes), and impatient users might not give it a chance to appear. Too short a timer (for example, one millisecond), and this dialog may appear and disappear a lot during regular browsing. Again, the goal was to get information about real world browsing to improve IE’s responsiveness and reliability.

Based on the initial, Microsoft-internal, data after putting this in the product, we thought the experience was unobtrusive and overall better for users because it provides more information to improve the product. As more data has started to come in from external Win7 users, we’ve seen an increase in reports. We’re watching the data very closely to understand how well this works for the larger set of users. If we see data that makes us think this is not a good experience, then we’ll release (as we have before) an update to address it.

While we continue to track the telemetry, if you are debugging IE either with the IE Developer Tools or a debugger, and you attempt to interact with the IE window, there is a chance that you will see this dialog. Although this will not impact your debugging it may be more convenient to turn this dialog off. Or if you’re running Win7 RC and are seeing this prompt more than you should or would want to, you can turn it off by changing the following registry key:

HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main!HangResistance, DWORD, 0


IE Team

P.S. People who downloaded Win7 RC “early” may be running without a Compatibilty View list because the list for the Win7 RC is still working its way through the deployment system. Depending on the sites you visit, you may or may not notice its absence. It will be available soon.

Comments (25)

  1. EricLaw [MSFT] says:

    For anyone who doesn’t understand the (geeky) instructions above, simply import the following registry script:

    Remember, this only applies to Windows 7 RC users.

  2. techbiz says:

    I am the webmaster for, and when I upgraded to IE8.0, suprise!, surprise!.  Apparently support for .gif format graphics has been dropped.?!  You need to warn anyone creating graphics on their webpage that no one will be able to see them in IO8.0.  They will need to make everything a .jpg to be seen.

    Was this intentional?  Compatibility does not correct for this.

  3. ieblog says:

    @techbiz: No, support for .GIF images has not been dropped, and the GIF files on look fine.

  4. Stefan says:

    Is there a way to get this Message on Vista based systems?

    If not, it would be really cool if you be willing to made an update available to add this functionality on non-W7-systems.

  5. If you are looking to follow this series, be sure to subscribe to my RSS feed at http://feeds.jasongaylord

  6. Dave says:

    That’s nice…how long is the timer set for by default, and how do I change it?

  7. ASPInsiders says:

    If you are looking to follow this series, be sure to subscribe to my RSS feed at

  8. Catto says:

    Hey Now,

    Never knew about Telemetry

    Thx 4 the info,


  9. Andrew says:


    love accelerator translate

    but not quite pleasant to use yet

    u see, i want to translate

    from japanese into english

    i block the font,

    i have to wait the translate service on

    then i have to select the language from to

    here the problem start

    when i block another font,

    i have to do the same thing over and over again


    this still on the same page !

    why not translate the whole site u ask ?

    because thats not what i want to do

    to me block the font is like using color marker on real life

    I HATE TO SELECT FROM TO LANGUAGE THOUSAND TIMES on same page or even better until i change the default or where the hell place to change FROM TO …..

    hope helps

  10. hAl says:


    Would that have something to do with the locale you have set or the language the websitie defines the text ?

    If I select your above reaction and use the live translate accelerator it automatically translates direct from English to my personal firstlanguage choice without having to select that choice.

  11. Vygantas says:

    Yes, they dropped .gif support, but on Windows, not IE

  12. Duryodhan says:

    What do I need to do to make you guys start working immediately *FULL ON* on IE9 instead of taking a long vacation like you did after IE7 RTM?

  13. EricLaw [MSFT] says:

    @Vygantas: I have no idea what problem you’re having, but no, neither IE nor Windows "dropped GIF support."  GIF images display throughout all versions of Windows and IE.

    @Duryodhan: As someone who has worked on IE for nearly 5 years, I can assure you that there was no "vacation" after IE7, nor was there one after IE8.  Dean’s "What’s next" section ( describes how we’re approaching the task of delivering the world’s most broadly used browser.  In addition to the IE9 work, we’re obviously working hard to deliver IE8 in Windows 7, which contains a number of features unique to that platform (


  14. says:


    I think some people hope that the IE development was more like Silverlight. Right when they finish one version, the beta of the next version is already available.

    Which does beg the question of what integration of Silverlight is going to make its way into IE. Like the JavaScript DLR, for example.

  15. Franco says:

    Please add this feature to IE8 for Vista. Thanks

  16. IE Team,

    Please forget about telemetry for a min.

    It is extremely difficult to understand why IE 8 RTW was released with known, reproducible and testcase-ed application hang (cpu %tage activity maximized due to infinite execution loop) bugs.

    In my opinion, there is no acceptable justification whatsoever for releasing IE 8 with known and reproducible hang bugs. We filed bug 366200 (september 2008) and bug 414807 (february 2009).

    Reproducible hang bugs should be considered blockers, as very serious bugs, with an higher severity, higher gravity; I know they would be treated as such in other browsers.

    regards, Gérard

  17. Dan says:

    Gerard, no software is perfect, and all software ships with bugs.  There’s an interesting discussion (with links) on this topic here:

    There’s an obvious "acceptable" justification for MS shipping with such hangs– they had more important things to fix.  

    Just because you can write HTML that causes users not to visit your page doesn’t mean the browser has to fix it… you could just put up a worthless / annoying web page and end up with the same result.

  18. IEBlog says:

    As we described on Monday , the IE8 in Windows 7 RC includes additional tab “hang” reporting functionality.

  19. Jim says:

    i am having to type this from the browser on my phone because i just downloaded and installed the W7 RC tonight. i have installed several updates already, but i am having a major issue with IE8. it will launch ok, but then after about 5 secs, it crashes to the point where it is completely unreliable and i can not get on the web!!! will the registry key listed above fix this?!?!?

  20. Доступно обновление для IE8 в Windows 7 RC Как было написано в предыдущем сообщении блога , IE8 в Windows

  21. EricLaw [MSFT] says:

    @Jim, most IE crashes (across all platforms and versions) are caused by buggy browser addons.  Please see for troubleshooting steps.

  22. says:

    As we described on Monday , the IE8 in Windows 7 RC includes additional tab “hang” reporting functionality

  23. IE8 on Windows 7 RC: Boink Boink

  24. Andrew says:

    @ hAl

    how ?

    how to set it that way ?

    this my default


    try block more than once,

    u will see what i mean,

    u have to select from to language again and again

  25. Vygantas says:

    EricLaw [MSFT],

    I mean that when viewing pics via Windows Photo Gallery, it displays no animations.