In case you've forgotten, older versions of the Internet Explorer web browser are no longer supported following the browser's demise on January 12. It means no more security updates, or indeed any updates full-stop, or paid-for support options.
If you're still using versions 8, 9 and 10 of the browser, you're open to unpatched vulnerabilities going forward, which is obviously very bad news. Microsoft is urging folks to upgrade to Internet Explorer 11, so you can expect a nag box to appear in older versions of IE if you're using Windows 7 and Server 2008 R2. Microsoft is continuing to support IE 11 and Edge, which ships with Windows 10.
Redmond says that Internet Explorer 11 will be supported for the life of Windows 7, Windows 8 and Windows 10 – although it will doubtless encourage those using its newest OS to switch to the new Edge browser.
Microsoft observes that when it comes to businesses, not only are there security risks in continuing to use an old version of Internet Explorer past January 12, but compliance requirements may also be violated, which is doubtless also very bad news.
Microsoft has issued several warnings on upgrading IE in the past, and if you haven't heeded them yet, now's the time to finally make a move.