While the idea of a "portable" Internet Explorer (IE) sounds convenient for testing old websites or running legacy apps, the reality is complex due to how deeply IE was woven into the Windows operating system. The Reality of "Portable" Internet Explorer
This is the only legitimate use case for IE6 Portable today: Corporate IT departments still rely on legacy intranet portals written in ActiveX and VBScript—ancient beasts that will only wake up for IE. Hospitals, banks, and manufacturers keep a USB stick with IE6 Portable in a drawer somewhere, because rewriting that 1998 inventory system costs $2 million. internet explorer portable old version
Internet Explorer Portable Old Versions: A Guide to Legacy Browsing While the idea of a "portable" Internet Explorer