Problems with Enterprise Mode (IE Mode) in recent builds ?

Brass Contributor

We are using the Enterprise Mode Site List to open specific internal pages using the IE rendering engine. (Primarily for our ERP app which requires Java Web Start... Not supported under Chrome / Chromium.... )


This has been working perfectly almost two years. We were using it before Edge Chromium, and now too with Edge Chromium..... Until recently, this has worked very well.


In the past few weeks, the experience of opening pages in IE mode has become inconsistent. Sometimes the page will open in IE mode, sometimes the page will open in a standard Edge Chromium tab... If I look at the config in edge://compat/enterprise ... All the expected pages are listed with Engine IE11 mode listed (and the XML version number is current)... So obviously the browser is downloading the Enterprise Mode XML file from our internal web server without issue...


This all seems to have started with Version 86.0.622.38 ... And still seems to be happening in .48 too (the latest release build).  Often times opening a new Edge session will cause the IE Mode sites to open correctly in IE mode again.    Also, using the compat/enterprise "Force Update" button will also cause the session to work correctly again.  (But the SiteList has not changed in more than 6 weeks.)


Is there anything I can do to troubleshoot why Edge is not opening the designated pages, using the correct mode?

25 Replies

@jpochedley Hi Joe - Thanks for reaching out!  I just talked to the IE Mode team and we've had a few other reports from customers with very similar issues all starting around V86.  We've been trying to investigate but I don't think we've been able to get a consistent repro.  


It would be very helpful to get your logs, repro steps, traces and other information we can use to troubleshoot.  Would you be able to file a customer support request?  They should be able to work with you to gather the necessary information for our team.  Thanks for your help! 




FYI:  @Shilpa_Subramanian 


Unfortunately I cannot repro the issue reliably myself. It seems to happen intermittently. This far i have not been able to figure out a set of actions that can make the problem happen consistently.

Let me know what logs I can collect which can help troubleshoot the issue.

I do not know whether I can open a paid support request, or whether we have available VL support requests. I will need to check with the team.

Hi @jpochedley, Kelly_Y directed me to your post as we just started seeing the same issue.  My full post is here:
Edge Beta intermittently ignoring IE Mode - Microsoft Tech Community

I can reproduce the issue randomly if I keep loading the same site on new tabs in Edge Beta or Edge Stable.  The key is I have to keep opening a new tab and paste the site in the address bar and just keep doing so until one fails.  So @Kelly_Y  if you could let me know which types of logs or traces you need, I can start working on those.  Do you have any documentation on that?  Thanks!

I concur. The method you mentioned... just keep opening new tabs to IE mode sites, over and over, until it fails.... is the only way I can regularly repro the problem too...

I did open a case with MSFT... Unfortunately they did not reach out to me until 5 minutes before EOB for the day. (Of course...) So, I requested a call first thing in the morning on Monday.

In the interim, if @Kelly_Y can provide details on what logs I can collect before the call, that would be helpful!

@jpochedley @SteveSta  Hello!  I'll pass on your observations and how you folks were able to reproduce to the IE Mode team! 


@jpochedley Thanks for opening a support case!  But sorry to hear about the bad timing! :sad:


I'll check with team now to see what type of logs they suggest would be helpful.  Thanks! 



@Kelly_Y We opened a Premier case as well, but still looking forward to you sharing which logs would be best to provide.  Thanks!

Found in testing that if a site doesn't load in IE mode on a tab, that tab will never load it in IE mode, nor will it load any site in IE Mode.  It's almost as if that tab doesn't know what IE Mode is.  You have to open a new tab and try again on that new tab and hope the new tab works with IE Mode. 

The opposite is also true, once a tab loads a site correctly in IE mode, any site that is in the XML list for IE mode will work on that tab, even if you use that tab to go to a non-IE Mode site, that tab will leave IE mode for that site as expected, then if you go back to a site on the XML list it will load IE Mode as expected.  Issue seems to be related to the tab itself.

I shared this with the engineer working our Premier ticket.

@jpochedley Do you happen to see this behavior as well?

@SteveSta Yes, what you describe has generally been my experience, though again it's not 100% consistent.  Occasionally navigating from one IE Mode page (opened incorrectly) to a second IE mode page (opens correctly)....    Though I have never seen the reverse... Seems that once a tab understands IE mode, then that tab always works correctly.


I have started working with MSFT on the case.  The first thing they asked me to do was install Fiddler and capture the problem.   Of course, once I installed Fiddler on two different test machines, I cannot repro the problem at all on either machine.   Works 100% correct on the test systems after Fiddler is installed.  

@jpochedley  @SteveSta  Hello!  Would you both be able to share your Support Request Number?  I want to pass it on to the IE Mode team.  Thanks! 





@jpochedley @SteveSta The IE Mode team has been investigating.  Would you be able to try run MS Edge with the command --disable-features=msUsePrerenderNTP and see if that fixes the problem?


Let us know if that helps!  Thank you! 



@Kelly_Y  Can you confirm how to properly add the switch?   Does it go on the command line directly, or does it need to go between the --flag-switches-begin and -end switches?


For example:

"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --profile-directory="Profile 1" --flag-switches-begin --disable-features=msUsePrerenderNTP --flag-switches-end



"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --profile-directory="Profile 1" --flag-switches-begin  --flag-switches-end  --disable-features=msUsePrerenderNTP


My case # is 120102624006978 Thanks

@SteveSta - Thank you!  


@jpochedley - Here is the recommendation from the IE Mode team: 

The easiest way is to click the Start button, Run and type in: "C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --profile-directory="Profile 1" --disable-features=msUsePrerenderNTP


Let us know if you have a chance to test!


If the command --disable-features=msUsePrerenderNTP fixes the issue for you folks, the next update being released to MS Edge Stable V86 should include the fix.  



@Kelly_Y  Thanks...   After my last message, I made the assumption that the CMD line switch was exactly as you confirmed... 


Since then, I've run the switch on every browser session I've started, and passed the info along to three  internal colleagues in our org for testing...  So far (obviously with limited testing of only a couple hours), we have not been able to replicate the problem when the --disable-features=msUsePrerenderNTP switch is used.

@jpochedley Great!  Sounds like early results from your testing have been positive! :smile:  



@Kelly_Y  I'm also seeing that with using the command line --disable-features=msUsePrerenderNTP when launching Edge Beta, I can't reproduce the issue either, so that's a good sign.  I'd be more confident if I could reliably reproduce the issue in the first place, but good to see this is also helping others.  looking forward to the update!  :)  Thanks!

@SteveSta Thanks for following up with your testing results so far!  Glad to hear the issue is not reproducing.  I'll plan to circle back here once I get the version number that includes the fix.  



@jpochedley @SteveSta Happy Wednesday!  Got word from the IE Mode team that the fix was released yesterday to the Canary Channel and will get to Stable next week.  Thanks! 



@Kelly_Y @jpochedley I know a fix is on the way, but still wanted to share.  the Microsoft engineer on my premier case for this said he can reproduce the issue as well, and he can repro it 100% of the time by doing the following:


Repro Steps:

  1. Open a tab, navigate to a non-IE mode site
  2. Leave the browser idle for 5 minutes
  3. Open a new tab, navigate to an IE mode site

It seems after leaving the browser idle for 5 minutes or so, that very next tab that you open, no matter what you navigate to first, will never open a site in IE mode.  The next tab after that will though, but it must be opened without the browser being idle.


This helped me repro it more consistently as well, and I wasn't able to repro it using the command line you shared, --disable-features=msUsePrerenderNTP so that's a good sign too.


He wasn't aware there was a fix on the way though, but is looking into it from his side as well.  Thanks