How To Enable Internet Explorer Legacy Mode Using Microsoft Edge This article will walk you through enabling the legacy Internet Explorer mode with the Microsoft Edge browser. This may be necessary for certain web pages that are running older versions of a program or are required by vendors.Enabling Legacy Mode Open the Edge Browser Open the Settings Menu in Edge by selecting the 3 dots in the top right of the browser window and select Settings Select the Default browser Menu Set the drop down value to the following Allow sites to be reloaded in Internet Explorer mode (IE mode) - Allow Select Add - a field will appear enter the website you are needing to access in Internet Explorer. Once added select Add again. Note the date the URL provided will be expire. If your URL exception expires you can reactivate the access by repeating step V(5) and 30 days will be added.