Multiple versions of Windows 10 are running out of support on October 14, 2025. This is an important date because some other Microsoft products are reaching end of life (EoL) at this time too. These include Skype for Business Server 2015, Skype for Business Server 2019, Skype for Business 2016, Skype for Business 2019, Exchange 2016, and Exchange 2019. The good news is that Microsoft has now announced Extended Security Updates (ESU) programs for many of these products.
Microsoft has published advisories for Exchange 2016 and 2019, along with Skype for Business 2015 and 2019. These are fairly identical in nature, as they deal with services in the same domain. Apparently, customers have informed Microsoft that they are in the process of migrating to Exchange Subscription Edition (SE) and Skype for Business SE, but as they finalize these migrations, they require a few extra months of security updates beyond the October 14 deadline.
The Redmond tech firm has decided to grant these extensions, with a few caveats. For starters, this ESU initiative is not a general extension of the support lifecycle, so it is not available for everyone. Organizations are requested to contact their relevant Microsoft representative from August 1 to secure an additional six months of security updates (SUs). The Microsoft representative will provide a quote based on the per server cost.
Additionally, the tech giant will only offer SUs for Critical and Important vulnerabilities, as defined by the Microsoft Security Response Center (MSRC). These updates will be provided privately to customers enrolled in ESU, they will not be provisioned through Windows Update or other public repositories. If there are no severe security issues reported, no SUs will be provided, but Microsoft will check in with customers every Patch Tuesday just in case.
In a rather stern manner, Microsoft has told customers this six-month ESU will not be extended past April 2026 and nobody should even reach out to discuss this topic further. As such, the firm has recommended customers to speed up their migration processes to Subscription Edition for both lines of products, rather than relying on the ESU extension.