Microsoft has issued a reminder to system administrators that Internet Explorer mode in Edge will receive support only until the end of 2029, urging organisations to begin modernising legacy systems that depend on Internet Explorer technology. The move is significant because many enterprises still rely on IE mode to run outdated web applications, and the company warns that these modernisation projects can take years to complete, making early planning essential to avoid future disruption.

IE mode allows organisations to continue using legacy websites within Edge rather than relying on the retired Internet Explorer browser, using the Trident MSHTML engine from Internet Explorer 11. Although Microsoft first announced this end-of-life deadline in 2021 and has committed to providing one year's notice before retiring the feature, organisations that fail to migrate may face security, compatibility, and compliance risks. Internet Explorer itself debuted in 1995, and whilst traces of it will persist through various Windows distributions (such as Windows 10 IoT Enterprise LTSC 2021, supported until 2032), Edge's IE mode is likely to be retired considerably sooner.