Tomorrow Microsoft will withdraw support for all but the final version of its Internet Explorer (IE) web browser.
But while the technology giant may have signalled more than a year ago that it would stop supporting older versions of IE, large organisations are struggling to wean themselves off soon-to-be insecure, legacy releases of the browser. It is a reminder of how slow businesses can be to let go of outdated technology and echoes the difficulty firms had in moving from Windows XP, even after it fell out of support in 2014.
A case in point is the National Health Service (NHS), one of the largest employers in the world, with more than 1.3 million staff in England.
Every doctor's surgery and hospital in England relies on a Information Services Portal (ISP) to access information about drug prescriptions. Unfortunately this portal doesn't officially support the latest version of IE, and has only been certified as being fully compatible with the older, soon-to-be unsupported versions of the browser.
The NHS says it will soon complete work to guarantee the still-supported IE11 is compatible with the portal and that Firefox or Chrome can be used as an alternative in the meantime.
"The NHSBSA has undertaken a review of all our systems. Compatibility testing for the ISP is in its final stages and initial findings suggest that there are no compatibility issues between ISP and IE11," said a spokesman for the NHS Business Services Authority.
The situation the NHS finds itself in is yet another example of the difficulties that large organisations have in updating line-of-business applications at scale, according to Bharat Mistry, cyber security consultant at Trend Micro.
"First and foremost is that at scale factor but also, if you look at some of these applications, they may not have the developers available. The people who originally wrote the code may no longer be with the organisation to take it further," he said.
Organisations can be reluctant to update business-critical software for fear of breaking it, particularly in the banking sector, he added, leaving them in a situation where they have to take steps to mitigate the risks of running apps and services on unsupported platforms.
According to third-party stats a surprisingly substantial chunk of people still use older versions of Internet Explorer, almost one in five web users according to figures from Netmarketshare - although other sources put the proportion lower. Microsoft is trying to ensure that users of older versions of IE update to 11 or to its successor Edge, adding a nag message encouraging users of older IE versions to switch.
The availability of enterprise mode in IE11, which allows sites and apps to run on an emulated version of IE 7 or 8, will help any organisations lagging behind on support for the final version of IE.
The difficulty large organisations are expected to have in supporting IE11 echoes the trouble large organisations had in moving from Windows XP.
When Microsoft dropped support for XP in April 2014, more than three-quarters of businesses in the UK were still running the venerable OS somewhere within their IT estate, according to one survey.
The US Navy agreed to pay Microsoft at least $9m for a custom support deal that would let it continue running Windows XP until July of this year, in order to keep using a number of legacy applications that require the 15-year-old OS. Similarly the UK government struck a deal with Microsoft for extended support for Windows XP for one year after support ended, with the government recently refusing to answer questions about whether some departments are still running the OS today.
Nick Heath is chief reporter for TechRepublic. He writes about the technology that IT decision makers need to know about, and the latest happenings in the European tech scene.