IE9/11 freezes in some situations after installation of KB2962872


  • Hi!

    In the last patch day Microsoft released KB2962872 (

    It includes a security update for all Internet Explorer versions.

    This morning one of our applications which depends on IE starts showing a strange behaviour. When opening modal dialogs in a cascade IE freezes and the application was not really useable. It tooks seconds to render or resize a modal dialog. After closing a dialog the parent dialog was not reachable for seconds.

    By deinstalling the patch, the problem was gone.

    Our application has much code in it so we tried to reduce the code for reproduceable demo, which can be found here:

    Just open the demo and click on the button "A", which opens a modal dialog with the same link. Click on the "A" button in the dialog to open an additional dialog... by opening 5-8 dialogs the behaviour should occur: Resizing is very
    juddery and closing a window will freeze the application for some seconds. Without KB2962872 installed you can open nearly hundreds of windows without any problem.

    We could reproduce this on IE9 (9.0.8112.16421 / 9.0.29) and IE11 (11.0.9600.17207 / 11.0.10) on Windows 7.

    How can be report this bug to MS or is there a workaround but deinstalling the update?


    Wednesday, July 09, 2014 1:32 PM


All replies

  • Hi Jan,


    for the proper way to use showModalDialog

    var retval = window.showModalDialog(dialog, varArgIn, varOptions);

    use varArgIn='' I/o null. (OT: null is Russian for zero, its not a zero length string).

    as the method name suggests Modal means Modal.. you should consider a different design pattern.

    additionally, I cannot reproduce the issue...

    go Tools>Internet Options>Security tab, click "Reset all zones to default"

    and also

    Repeat your testing in noAddons mode.

    There are security zone settings in MSIE browsers for scripted windows and IE Popup blocker settings....

    If you have a third-party popup blocker installed (your Google Toolbar?) it can change outcomes for scripted windows.

    You can turn off the GTB's popup blocker from the 'Spanner' Icon on their toolbar... you don't need 2.

    bug reports or feature requests or feedback for the IE Team should be posted to

    In you case I don't think its a bug, rather your IE and IE Addons configuration. IE Security urpdates are mostly directed to vulnerabilities and exploits found in third-party addons.

    Questions about html, css and scripting for website development should be posted to the IE Web Development forum

    Include with your questions a link to your website or a mashup that shows the issue.

    If you are using a non-public domain, contact MS support ( ) in the first instance to arrange for a MS engineer to access your networks to debug your pages.

    Please validate and correct any markup errors....

    your test page A.htm has many errors.... you can validate and correct your markup errors at



    Thursday, July 10, 2014 1:59 AM
  • Hi Rob,

    Thank you for your reply!

    The script/demo is a simple example that reproduces the issue. Its works without problems on all IE versions before KB2962872!

    A "more easy to reproduce demo" is available here:

    The script simply opens 15 dialogs (ensure that you allow popups). If you open this with IE (having the latest update - 11.0.9600.17207) you will notice that it will become very slow as of the 6th or 7th window. Closing the dialogs will be also very hard.

    We could reproduce this on Win7 (IE 9, IE 11) and also on Win 8.1 (IE 11).

    It's not related to any design pattern, nor not well-formed markup... it looks like a memory problem which was introduced in KB2962872 and actually is a show breaker for an old application of us :-/


    Thursday, July 10, 2014 12:29 PM
  • Hi Jan and Rob

    We totally encountered the same problem, and it really hurt.

    There is no choice but told our customers to uninstall KB2962872 for the time being.

    I tried the A2.html file locally, and you could see that the cpu goes very hight when IE freezes.

    Hope there will be some other ways to make showModalDialog works fine. 



    Friday, July 11, 2014 1:06 AM
  • Hi Leo,

    I'm "happy" to found someone with the same problem!

    I would please you to commit your experiences to this bug report:


    Friday, July 11, 2014 10:26 AM
  • Hi Mojo

    Thanks for pinpointing which KB goofed up my computers so badly!

    Here's how my Win7 looked for about 10 minutes.  I didn't think I'd ever be able to get back onto the internet with it, but it eventually recovered enough to do that.  (IE was still malfunctioning in various ways).


    Here's how your test page looked with Win7+IE10 after opening multiple windows (crashed IE).  It recovered perfectly after removing the KB.


    Here's how your test page looked with Win 8.1+IE11 after opening multiple windows (crashed IE).  It recovered perfectly after removing the KB.


    I think that person (IECustomizer MVP) who responded to you first didn't try very hard, in his eagerness to deny the bug.  He probably doesn't recognize how unproductive and offensive it is to be on the receiving-end of a contradiction, complete with self-important condescending off-topic lecture, to a person's bug report of something this obvious.


    Here is a matching complaint about this same KB update.  With matching replies.



    You may click the [Report as abuse] button to alert forum mgmt of any post that you feel is intended to impede your use of these forums.  In particular, if you see that it is contrary to MS Community Code of Conduct terms to "Keep conversation threads on track and constructive" or attempts to "Divert or change a thread for [your own] purposes".

    Friday, July 11, 2014 1:55 PM
  • Ok, we are not alone! :-)

    Please participate at the bug report to give it some more attention:

    If you can reproduce this issue (which should be the case for everybody that had installed the KB) please commit this in the bug report.


    Friday, July 11, 2014 3:51 PM

    If you can reproduce this issue (which should be the case for everybody that had installed the KB)



    That was a gentle indictment.     ; )

    Friday, July 11, 2014 4:50 PM
  • Trying to sign in for your feedback report and of course, that's not working for me to report I have hundreds of customers reporting issues with IE9,IE10, and IE11 not being able to use my companies website.

    I'll keep trying.

    Monday, July 14, 2014 1:35 AM
  • Hi Jan,

    I have take test on my lab machine which install Internet Explorer 9 and Internet Explorer 11 on Windows 7, the result is they work fine after install KB2962872.

    Thus I suspect this might be caused by the incompatible between your application and this update.

    However, I suggest you check and install all available Windows Update. And then perform a clean boot to start your Internet Explorer to check the result.

    If the issue still persists, please remove this update temporarily.

    Karen Hu
    TechNet Community Support

    Wednesday, July 16, 2014 2:29 AM
  • Hi Karen,

    Thanks for your feedback! I'm really wondering that you are the first person that is not able to reproduce this issue... :-/
    Everybody I send to the test page reported the same behaviour if the update is installed (most of them started without the update/a working version). That's very strange.

    Just to be sure: You also tested this example: ? (enable popups!) shows the problem without interacting at all. Some of my test peaople missed to open more than 2/3 windows (in which will not show the problem.

    Actually the only workaround is to remove the update.


    Wednesday, July 16, 2014 1:12 PM
  • Hi Karen

    Please take this seriously,
    I can remove this update on my workstation, 
    but my clients can't due to the security policy of their company.

    All we're able to do right now is keep apologizing.

    It's really huge for us.


    Thursday, July 17, 2014 6:56 AM
  • please use this simple test case:

    Thursday, July 17, 2014 12:13 PM
  • please use this simple test case:

    And what should we expect? Actually I'm unable to reproduce the mentioned issue on this link... so why do you post this without any detailed information here?! It's really very unproductive in view to bring MS to look into that issue if others post undocumentated "test cases"... :-/
    Thursday, July 17, 2014 6:45 PM
  • I have take test on my lab machine which install Internet Explorer 9 and Internet Explorer 11 on Windows 7, the result is they work fine after install KB2962872.

    @ Karen

    The demo could be constructed a lot more clearly IMO.  E.g. they could have put a line into the text which explains that they want the button on the inner page clicked to produce their "cascade".  Further, they could have actually offset the new window to demonstrate that there was a cascade.  So, after figuring this out I can reproduce a symptom which looks like the problem description but for me (on a Surface Pro 2 with 8 GB RAM) the slowdown only starts at iteration 12.  I stopped when I reached iteration 20.  The next interesting thing to observe happens when you try to start backing out of all that.   <eg>



    Robert Aldwinckle

    Friday, July 18, 2014 3:18 PM
  • So Karen

    Are Microsoft actually investigating these KB2962872 issues or not?

    There is most certainly something badly broken with the rendering in IE11 once this update is installed. Uninstalling the update reverts IE11 behaviour to it's previous speed.

    Please advise.



    Sunday, July 20, 2014 11:56 AM
  • Hi folks.

    We are aware of this issue and we have an active investigation under way. We have added performance as an issue to KB2962872.

    Thanks and regards.


    Mark Feetham Senior Program Manager Internet Explorer Product Quality

    Monday, July 28, 2014 9:44 AM