The impending End of Life (EoL) deadlines for various Microsoft applications and systems are becoming a pressing concern for many organizations. Recently, there has been a notable surge in inquiries from large enterprises seeking advice on upgrading Microsoft Teams and legacy technologies, particularly over the past month. This heightened activity underscores a palpable urgency among businesses to tackle their aging applications and operating systems, all of which are set to reach their official EoL by 2025. With Windows 10, Office 2019, and Exchange Server 2019 all facing end-of-support by October—merely six months away—companies are confronted with critical decisions to mitigate operational, security, and compliance risks.
This rush to address EoL concerns stems not only from the immediate risks associated with outdated technology but also from a broader mindset that equates EoL with high-risk scenarios demanding urgent upgrades. However, it is essential to recognize that this is not a singular event; as one product is upgraded, another inevitably approaches its EoL. Thus, businesses must adopt a perspective that views EoL management as a continuous activity. In some cases, maintaining EoL systems may be the most prudent approach, provided they are transformed into compliant and secure versions.
For instance, a significant portion of NHS computers continued to operate on Windows 7, despite the government’s goal to upgrade all PCs to Windows 10 by January 2020. They utilized Microsoft’s extended support period to complete the transition by 2021, only to now face the upcoming deadline for upgrading Windows 10 by October.
As the end of support deadlines draw near, organizations may feel compelled to overhaul their applications and systems to function on modern infrastructure, which could involve complex refactoring or the integration of entirely new application suites. However, given that these applications are often critical to business operations, any disruption could pose a severe risk.
Supporting out-of-support applications
Statistics from Statcounter reveal why companies are actively seeking guidance. As of January 2025, the market share of Windows desktop versions in the UK was evenly split between Windows 10 and Windows 11, each holding 49.4%. This indicates that half of all desktops are nearing their EoL. Given the complexities involved in migrating IT infrastructures for large organizations, this percentage is likely skewed even more towards Windows 10.
In response to these concerns, dedicated EoL hotlines have been established to provide companies with swift, tailored guidance on preparing for EoL transitions. This includes strategies for migrating existing applications, such as Microsoft 365 products, that are approaching their EoL, ensuring their compatibility moving forward. Importantly, the process of transitioning existing out-of-support applications onto managed and supported servers can be executed with minimal disruption to operations. However, the complexity of this transition necessitates that companies possess the internal resources, expertise, and guidance to undertake such an endeavor effectively.
The industry-standard ‘R approach’ employed by cloud providers encompasses six distinct methods to evaluate a company’s IT estate and facilitate migrations for EoL software. For example, ‘rehosting’ involves transferring applications to the cloud without substantial modifications, while ‘retiring’ identifies applications that are no longer useful and can be decommissioned. Each method serves different contexts and requirements.
For organizations with unique or complicated needs, partnering with an external specialist can provide a more efficient and cost-effective solution for navigating this critical undertaking.
Keeping Windows EoL front of mind
As several end-of-support deadlines for Microsoft products loom in 2025, organizations are increasingly eager to understand how to swiftly and securely upgrade their Microsoft Teams and legacy applications. However, the anxiety surrounding the risks of inaction can lead to costly upgrades and the complete overhaul of application suites—processes that can themselves introduce significant disruption and risk.
Instead of altering out-of-support applications directly, companies can consider migrating them into secure and managed operating environments, whether on-premises or in the cloud. With a considerable number of desktops still operating on Windows 10, this approach allows for continued operations while applications are transitioned into these environments. It is crucial to clarify that this does not imply embracing EoL software as is; unmanaged or unsupported software inherently poses risks. Rather, it calls for a shift in mindset regarding how EoL is perceived, recognizing that the applications themselves need not be the core issue.
Migration strategies like the R process empower companies to assess their IT estate and implement necessary changes. For those whose needs do not align with standard methods, seeking assistance from specialized firms can facilitate the transition. Moving away from EoL is a journey that, for many organizations, will unfold gradually, reflecting the intricacies of legacy applications. Just as one cannot simply uproot legacy systems without careful planning, organizations must remain vigilant about EoL deadlines and the challenges posed by their applications before it becomes too late.
This article was produced as part of TechRadarPro’s Expert Insights channel, where we feature the best and brightest minds in the technology industry today. The views expressed here are those of the author and are not necessarily those of TechRadarPro or Future plc. If you are interested in contributing, find out more here.
