Internet Explorer EOL – What it means for Enterprise Legacy Applications

This year Microsoft intends to end its mainstream support of its long-lived browser, Internet Explorer. From June 2022, the IE11 desktop application will be disabled and redirected to Microsoft Edge.

Microsoft Edge Group Program Manager Sean Lyndersay confirmed the company’s stance in a blog post in May last year, stating, “Over the last year, you may have noticed our movement away from Internet Explorer (“IE”) support. Today, we are at the next stage of that journey: we are announcing that the future of Internet Explorer on Windows 10 is in Microsoft Edge.”

Lyndersay said that Chromium-based Edge provides a better, more secure browsing experience than Internet Explorer, and we can only agree with that. 

However, some applications, particularly those based on Java Applets, Adobe Flash, or custom IE implementations of HTML/JavaScript/CSS, only work reliably on this browser. This creates a significant problem for enterprises that still need to preserve access to these applications.

What does this mean for your Legacy Applications?

According to a Microsoft commissioned survey, companies on average use 1,678 legacy applications. Many of these will be browser-based and require Internet Explorer. 

From June 2022, the only way left to access these applications on Windows will be to either keep an unsupported instance of Internet Explorer 11 locally or to use Edge in “Internet Explorer mode”.

What is “Edge Internet Explorer Mode”?

Internet Explorer mode was created for organisations that still need Internet Explorer 11 access for backward compatibility with existing websites, but want or need to move to a modern browser experience. Microsoft believes Edge IE Mode is the solution for organisations to use one browser, both for legacy apps as well as for modern browsing.

“The new Internet Explorer mode … seamlessly render[s] legacy IE-only content in high fidelity inside of Microsoft Edge, without the need to open a separate browser or for the user to change any settings manually,” Kyle Pflug, a senior program manager lead who heads the developer ecosystem team, asserted in a post to a company blog. 

Sites will typically need to be specifically configured (usually via group policies – GPOs) to automatically use IE mode, otherwise, they will be rendered via Edge. It is very highly recommended to only allow Trusted Sites to be opened via IE mode, as the security model of Edge IE Mode is unfortunately essentially the same as old Internet Explorer.

What about third-party users and third-party applications?

The demise of Internet Explorer will have a massive impact on third-party and occasional users of Legacy Applications. This is because a local installation may be impossible, or they do not have the rights to configure Edge to run a specific third-party application in IE Mode, which is common within industries where you may be dealing with highly secure IT environments.

So what are your options if you need external users to use your Legacy Application, or if you need to access third-party applications occasionally? 

  • A complete rewrite of the application (if internal) – this option is often impossible (if it is an external application) or very impractical, due to cost and timeline implications.
  • Abandoning the application entirely – this might be simply impossible for mission-critical applications, or in case of accessing external applications, especially if provided by the government or the public sector. 
  • Use modern HTML5 conversion technologies to preserve access to the applications from modern browsers.


An alternative: preserve accessibility to your Legacy Applications on modern browsers with Leaning Technologies tools

Leaning Technologies’ solutions allow companies to preserve mission-critical legacy applications written in Java, Flash and C/C++, by automatically migrating them to HTML5 and WebAssembly, making them accessible from any modern browser, whether they are internal, public-facing, or even third-party applications.

Our technologies have given organisations, such as Ticketmaster, Euronext, Leonardo and Mitek an alternative option to rewriting native applications to HTML5/JavaScript or to discontinue mission-critical applications. 


We make solutions for migrating Java Applets and Applications (CheerpJ), Flash applications (CheerpX for Flash), and C/C++ (Cheerp). Our tools are all based on WebAssembly, a web standard accepted by any modern browser, including Google Chrome, Microsoft Edge, Mozilla Firefox, and Apple Safari. 

By harnessing the power of WebAssembly, and our experience in programming languages and virtualisation, we make conversion tools and emulators that translate native Desktop and Mobile applications into standard web applications that can be used by any device with a browser, irrespective of its operating system and browser vendor.

Any existing Java, Flash or C++ applications that are mission-critical, and took years to be developed, can be ported and migrated to HTML5 automatically, with minimal intervention. Execution of the application will continue to be client-side, sandboxed in the browser for maximum security, and won’t require any complex cloud infrastructure.

Get in touch to find out more!

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