Checking for Incompatible Add-ons With RC1

Hi there, it’s Max again, and with the availability of our first release candidate (RC1) build of IE7, I wanted to explain a new feature some of you might have seen when installing and running RC1.   As an overall goal for IE we want to build the most stable and reliable browser that we can.  We know that we sometimes make mistakes that cause crashes or hangs, but we actively try to find and fix the cause for as many as possible.  Tools such as Windows Error Reporting help us a lot here, and we encourage everybody to hit “Send Error Report” whenever you encounter a problem.

Through the help of Windows Error Reporting, as well as other feedback we’ve heard here on the blog as well as on Channel 9, we’ve discovered a few add-ons that can cause problems for ie7.  We investigate all that we find and for those issues that we can’t fix ourselves we attempt to contact the provider of the add-on and alert them to the issue as well.  Unfortunately, there are some issues that neither the provider of the add-on nor us can easily fix, and for those issues that cause IE7 to crash or hang we felt we needed to provide some mechanism to help you, the user, keep browsing.  With RC1, we’ve introduced a new feature that proactively looks for any installed add-ons that cause issues and warns the user on startup.

For example, we know that version 1.2 of the MSN Toolbar causes IE7 to crash in certain circumstances.  With RC1, if you have this version installed, you will see this when you start IE:

Add-on Compatibility Warning

The buttons allow you to:

· Check to see if a new version of the add-on that potentially addresses the problem is available

· Start IE with the add-on enabled

· Disable the add-on and start IE

For add-ons that both Microsoft and the add-on provider agree cause particularly serious issues (an example might be preventing IE from even starting), we don’t provide the ability to run with the add-on enabled.  An example here is version 1.0.1507 of the IE developer toolbar.  This old version caused hangs and crashes in IE7.  If a user has this old version of the toolbar installed when upgrading to RC1, this is what they will see:

Add-on Blocked Dialog

Of course there are lots of extensions out there for IE with more being written all the time (check out some that we’ve written about before) and we don’t have the resources to be able to test all of them on all versions of IE (both 7 and beyond), so we know our list of extensions that we watch for won’t be complete.  If you’re having problems with IE7 running reliably on your machine, check out this previous post on Troubleshooting and Internet Explorer’s (No Add-ons) Mode.


Max Stevens
Lead Program Manager

Comments (44)

  1. silvia negreira says:

    pc hp pavilion 5410

  2. Ti says:

    Why don’t use all Windows XP styles? Please update to match Windows theme properly including XP styles.

  3. cooperpx says:

    Neat Stuff. This is exactly the sort of thing I expected the "send report to Microsoft" should do.

    Max, if I’m not mistaken, this would be the first project that is able to take advantage of this information between builds?

  4. Fduch says:

    It’s interesting do they put "hungapp" ones in trash?

  5. Bruce says:

    @EricLaw [MSFT] – No I don’t have any plug-in’s or toolbars installed. And when I start IE in ‘no addons mode’, the problem still occurs.

    I hope you could help out, because I sincerely thought this build of IE7 would fix the bug but it didn’t so yeah…it caused me to be upset…partially.

  6. J.A. Miller says:

    The bug database is hard to use, so here’s my feedback on the new release candidate.

    The IE 7 RC 1 setup program was terribly slow. I think it took around 15 minutes on my Thinkpad X41. Firefox, on the other hand, takes less than 1 minute.

    The menu functionality is broken. If I press Alt, T and then Alt again (to cancel), then the File menu becomes highlighted. It should not be. This is inconsistent with every other application in Windows.

    Also, the menu is at the wrong place. It should be at the top of the window, like other applications.

    I have the menu visible (to preserve my sanity). It’s looks really odd when I start up IE. At first the menu is not visible. Then all the controls are shoved down. It would be a much nicer experience if the controls would be positioned correctly when IE becomes visible.

    When I started up my browser, the address bar contains the text "about:blank". This text is completely meaningless. It would be much nicer to just leave the address blank.

    The text on the tab still flickers too much. I only have a 768 kbps Internet connection. When I surf to "", the text in the tab flashes from "Connecting…" to "Blank Page" to "Microsoft." The text "Blank Page" should not be displayed.

    If I press Ctrl+F and start taking immediately, some of the characters that I type are lost. I mean to search your blog for "Feedback" but ended up searching for "edback".

    The Options menu option (available under the Tools menu) should have an ellipsis so that it is consistent with Windows Explorer.

    OK, those are the problems. You did two things right: First, you eliminated the spinning "e", which was reminiscent of the Netscape era. You’re on up on Firefox. Adding tabs was a very good idea. It makes so that I can actually surf productively in Internet Explorer (it used to drive me crazy).

  7. Fduch says:

    @J.A. Miller "I can actually surf productively in Internet Explorer (it used to drive me crazy)."

    That’s not the case with me.

    I surf for sometime, then for example open Fotoshop. What I see? Oh! Again! I have only "File" menu, others don’t open.

    Right-clicking the taskbar. As I thought, no context menu.

    I close Fotoshop fast, because if I leave it like this My other app will start to crash.

    Closed it.

    Now I have my context menu back. Running Tsk manager.

    Just as I thought I have 2 uexplore.exe proxesses (While only 1 IE is opened) and one of them uses 5400 GDI objects.

    I close IE telling it to open tabs the next time. I pray that it really opens them the next time.

    I open IE again. Pages begin to load, some of them quickly turning into "Webpage cannot be displayed".

    Opening Task Manager. 1500 GDI objects.

    Now I can live for a while while IE slowly leaks.

  8. Dave Holloway says:


    Honestly IE team, what is the point of implementing these great features (addon checks, CSS support, tabs etc.) when half* the people who still run Windows use Windows 98 and Windows 2000 and cannot upgrade to IE7?

    Many of the people who read this blog are web developers. Typically, web developers are lazy people and like to write one line of CSS code that works for all browsers. We have all had sleepless nights trying to tweak our websites (be it with hacks, or conditional comments) so that they run on IE5 and IE6. The problem is that this process takes time (sometimes days or weeks) and IE7 will not change anything unless it works on older legacy operating systems too so that we do not have to code for IE5 and IE6 anymore.

    I have read

    and I consider it a poor excuse that:

    "IE7 relies on operating system functionality in XPSP2 that is non-trivial to port back to Windows 2000."

    I thought IE7 wasn’t meant to be tied to the operating system? Just delay the IE7 release a bit and do it! Please! This support can’t be that hard to do. Firefox (from, if you haven’t heard of it), even works on Windows 95 and still has great features.

    IE7 is a great browser. If it was the only IE browser, it would be greater. This little change would have thousands of web developer headache-hours.

    If IE7 budget is a concern, put up a PayPal donation page. I would bet that every web-developer who has spent more than 4 hours faffing around with Internet Explorer 5 and 6. would donate at least $10 (go on Dorward, you know you want to) for this support.

    Not everyone uses Windows XP, even if you do.

    Dave Holloway

    *maybe even 3 times more.

  9. Dave Holloway says:

    Whoops, typo:

    "This little change would have thousands of web developer headache-hours."

    "This little change would *save* thousands of web developer headache-hours."

  10. Robin says:

    Dave: pretty much every stat I’ve seen recently says that XP has something like 85% share of the Windows segment… It’s understandable that MS are focussing on this. Besides, it’s not like there aren’t decent alternatives (in Fx and Opera) available for older systems.

  11. Dave says:


    Are you a web developer and, if so, will you continue to code for Internet Explorer 5 and 6 when 7 comes out?

    The workload to badger these two browsers into displaying websites correctly is enormous. Even at 85% using XP, there are still going to be a lot of people using earlier Windows versions.

    I know Firefox is available for older systems. Given the choice I would install it on every system, but IE 5 is installed by default for every fresh installation of 98/ME and 2000 – not everyone is going to switch. – They are more likely to install Windows updates (i.e IE) rather than alternate browsers.

    Dave Holloway.

  12. Dave says:

    You say you can’t possibly check all add-ons so why don’t you do what Firefox does. Every extension is meant to supply a minimum and maximum version that they’re known to work in. If you install an unsupported version then Firefox asks if you want to update your extension. Combine this with a blacklist for extensions that don’t do this or are malicious then you’re set

  13. Bob says:


    The version of IE7 just before this RC1 would not work with OWA 2003. If I wanted to reply or forward an email that new window would just hang. But now with RC1, I can reply and foward. But it’s when I hit send, IE crashes and I send a crash report.  Any tips?

    It’s OWA2003 I’m accessing.

  14. cooperpx says:

    @ Dave

    Microsoft has already proven that they can cut out important swafts of feature from IE7 (look at the differences between IE7 for Vista and XP). Anything that is missing in Win2k could have been emulated or return ERROR_CALL_NOT_IMPLEMENTED.

    It is completely intentional that IE7 "cannot" compile for Win2k or prior. I think this is a mistake for Win2k.

    However, Microsoft is a business and they need a way to ensure that people upgrade. Microsoft doesn’t (directly) make money with IE … and this is just one of the carets they’re using to recoup their costs for the IE project.

    When you get tired of supporting IE6/5.5, just do what we did back in the day: detect the old browser and put up a plaque pointing them to Opera / Firefox 2.0 or before. (Mozilla is dropping support for 95/85/ME in 2007).

  15. Travis says:

    On the Feedback site, the upload file doesn’t work, and it claims to be due to a flaw in IE7.

    Has this flaw been fixed yet?  If so, what was it, and how can we test it?  Uploading files is a pretty important part of online forms!


  16. PatriotB says:

    "The Options menu option (available under the Tools menu) should have an ellipsis so that it is consistent with Windows Explorer."

    Actually I think IE got it right here.  You’re only supposed to use ellipses when more information is required to complete the command.  The command in this case is for showing Options; you don’t need any more information to show options, you just show it.  (Save As, on the other hand, needs more information before it can save: it needs a file name from you.)

    Windows Explorer is probably the one in the wrong here.  Along with lots of apps (e.g. Visual Studio 2005, for one).

  17. PatriotB says:

    "You say you can’t possibly check all add-ons so why don’t you do what Firefox does. Every extension is meant to supply a minimum and maximum version that they’re known to work in."

    That’s a great idea.  Unfortunately you’d have to enforce it from the start, and since the IE addon mechanisms date back 7-10 years, there’s not much they can do here.  Except use this kind of policy for any new mechanisms that are added going forward.

  18. Scott Jones says:

    All these behind the scenes features will be surely be appreciated by a certain segment, but the far larger segment of the population would prefer front scene improvements, like something so simple and yet user-friendly and intuitive as being able to close a tab without having to first switch to that tab as Netscape allows. Et cetera.

  19. TEK_GUN says:

    Two problems to me about IE 7, first off user interface. I dont like the fact that the user cannot move toolbar icons such as the  address bar or competely remove seach box as I use my Links and folders "a folder dedicated to search , tools, blogs , home portals etc. etc"….

    The user is stuck with the address bar on very top , Im used to centering the address bar and share that space with the "back-foward-refeshe buttons to the left sharing the same bar as compact as can be.

    Sorta like AOL software with my links folders on top

    Another UIF issue I have the inability to move "tab bar to bottom of the page competely and the fact it shares space unlike any other tabbed browsers avant , firefox they all give you option to put tabs on bottom and tabs DO NOT share any bar space they have there 0WN

    Last but not least I’m still using service pack xp2

    When i installed IE 7 Beta 2 it slowed down not only IE but my entire computer BADLY

    note; I havent been able to download IE 7 rcc or Beta #3 or whatever the current fix is called succesfully , I’ll wait til Vista hopefully these improvements UIF and other bugs will be fixed.

    P.S. just one question Can people who use Vista platform still revert back and use IE 6 if they so choose?

  20. I appreciate the idea of having this dialogue, but I hate it’s design.

    Why, for example, isn’t the title of the add-on in the bold title text? The title refers to "this add-on", but nobody knows what "this add-on" is at this point in the reading progress.

    The table with program, version and publisher is a bad idea, because at first glance it looks like information that only developers care about (even though it isn’t), and I, personally, would not expect the majority of users to read it. The long version string, and the long name (who really talks about "Microsoft COOPERATION" in every-day usage?) both are not helpful.

    Why can’t the dialog be something like "Version 1.2.5 of Microsoft’s MSN toolbar will not work correctly with Internet Explorer 7, and should be updated"?

    Lastly, the "Run Add-on" button is confusing. Should I do it, or not? Naming it simply "Run anyway" would probably be more clear.

    Most of this translates to the second dialog as well. Here, especially, I would wonder (if I hadn’t read this blog post) what is the difference between add-ons that cause the first dialog, and ones that cause the second? Also, why is this add-on blocked? Is it some kind of spyware? Why not simply "Foo will not work at all with Internet Explorer 7, and has to be updated"?

    Cryptic dialogs like these are the reason why Mac-users like me laugh about the Windows’ user interface.

  21. Mudanzas says:

    "Cryptic dialogs like these are the reason why Mac-users like me laugh about the Windows’ user interface." Im totally in agreement.

  22. Guy says:


    Not sure if this is the right forum, but just wanted to let you know there seems to be a rendering problem with some of the icons on the IE7 toolbar in large icon mode.

    I’d attach a photo if I could, but to explain it, the bottom border on the two arrows (forward/back) on the top left of the screen seems to be jagged and not very uniform (the top border is mostly rendered correctly).

    I’m running a Dell Dimension 4700 desktop with a Dell 17" LCD screen at 1280×1024 resolution, 32 bit color depth, Intel GMA900 graphics.

    You might also want to check out some strange error messages when viewing – frequent crashes when multiple tabs are open on that site too.

    Regards and thanks for all the hard work!


  23. Tricky says:

    Allowing us to enable ActiveX on a per site basis would be very helpful. Especially with all the malicious sites out there. I only want to run ActiveX scripts on sites that I trust. This would be good in corporations to enforce.

  24. Brutus says:

    Dave Holloway, you’re dreaming if you think that half of all Windows users use Win98 and Win2000.

    Check out these stats regarding OS share:

    Win2000 – 7%

    Win9x – 4%

    Win2000 – 6%

    Win9x – 4%

    Win2000 – 7%

    Win9x – 5%

    Win2000 – 4.5%

    Win9x – 3%

    (Above, Win9x refers to Win98 + WinME.)

    BTW, Firefox is dropping Win9x support, and you can only upgrade to Apple’s Safari browser by updating the OS.  So, IE7 not supporting very old versions of Windows is no different than what Firefox and Safari do.  I don’t think Opera supports Win9x anymore either (I’m not certain; they don’t make it clear on their site).

  25. Charlise says:

    Torsten Kammer, if you have suggestions on improvements, then just suggest them, rather than acting like a prosecutor, demanding answers (in your accusatory and smarter-than-thou tone) to your queries, "Why isn’t this?" and "Why can’t that?"  I mean, it’s not like you really want the answers to those questions (for the answers are obvious: the devs simply didn’t think of doing it your way).

  26. Thanks for informations.

  27. sid says:


    Firefox 2.0 will still be available for win9x users. However 3.0 will be w2k or better.

  28. Aedrin says:

    "We have all had sleepless nights trying to tweak our websites (be it with hacks, or conditional comments) so that they run on IE5 and IE6."

    Don’t speak for others when you can’t.

    If you spend that much time worrying about it, then you need to rethink what you’re doing. It does not take that much time and effort.

    Also, why support 5.5?

    "Firefox 2.0 will still be available for win9x users. However 3.0 will be w2k or better. "

    They barely managed to get an improvement in 2.0 compared to 1.5, and they’re already planning 3.0? They’re getting desperate… Let the Version War begin (again).

  29. Torsten Kammer says:

    Charlise: I’m sorry, I was a little sleepless when I posted this and would probably change the wording if I wrote it again.

  30. alice says:

    for those of us who might not be as computer literate as the rest of your audience, could you please direct me to a glossary of terms used in this instance?

  31. Francis says:

    One thought about add-ins and the tabbed browsing interface:

    Please make window management keyboard shortcuts take priority over those used by add-ins. When I have an Acrobat document open, I cannot change tabs (with CTRL+digit), nor can I close the window via CTRL+F4 or CTRL+W.

  32. Jeff says:

    Is this feature disabled on Limited Account?

  33. EricLaw [MSFT] says:

    @Travis: The file upload issue with IE7 was resolved in favor of appcompat in RC1.  Are you referring to the CONNECT site’s feedback form?

    @PatriotB: You are correct; the UX text standards were updated for Vista and going forward.

    @Scott Jones: Middle-click an inactive tab to close it.

    @cooperpx: If we did that, the browser would say "Error_call_not_implemented" on startup.  Everything from the UI to the core URI engine depends on newer, more secure APIs available in XPSP2 and later.

    @Tricky: Per-user ActiveX is a feature we’re looking at for future releases.  For now, the new ActiveX opt-in feature (plus protected mode on Windows Vista) offers quite a lot of protection from ActiveX misuse.

  34. Andi says:

    Good idea. However, can I just second Torsten Kammer’s comment about the wording? I think it’s a bit clumsy and could do with being looked at.

    Your example shown above, for version 1.0.1507 of the IE developer toolbar, seems to imply that the add-on being blocked is Internet Explorer itself. The only reference to the add-on in question is the version number, which most users will not recognise, especially your less tech-literate users.

  35. dr.bashir a khan says:

    Every time I installed MSN beta 3 and now the latest MSN7 It causes blocking of the other programmes especially Hp director, which will not open. so I had to uninstall them and the load up my Old MSN Beta 2.

    What is the problem are these the bugs as these easily get hanged up.

  36. Typhoon87 says:

    Agree with andi. Putting the app name as internet explorer seems to show that its blocking itself.

  37. Meio Bit says:

    O Firefox está cada vez mais perto de finalizar a versão 2.0. Hoje foi liberada a versão beta 2, que pode ser baixada diretamente do servidor deles. Entre as novidades estão corretor ortográfico embutido, sistema anti-phishing

  38. hAl says:

    I asume the name issue with the IE developer toolbar add-on as "Internet Explorer" is due to a poor naming of the add-on and not an issue occuring from the dialog.

    however I agree that the dialog info could be presented better.

    Also I really like the suggestion to make the "Run Add-on" renamed to "Run anyways" as pressing that implies the risk taken by the user when running the outdated add-on.

    And I also agree that the second dialog should give better info than "this add-on was blocked". "This Add-on is outdated and will not function properly with Internet Explorer 7 or higher" seems a more appropriate message.  

  39. One of the Microsoft MVPs, Robear Dyer, put together a great list of sites for info and questions about

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