Admins should bookmark the date if they want to keep Office apps and others in the Microsoft 365 fold protected with security updates. Two big events coincide on January 10 that affect Office services like ExchangeOnline, SharePoint Online, and OneDrive on Windows 7 Extended Security Updates (ESU) paid program and Windows 8.1. “On January 10, 2023, Windows 8.1 will reach the end of support. Also, on the same day, the three-year Extended Security Updates (ESU) paid program for Windows 7 and Windows Server 2008 R2 ends. While Microsoft 365 Apps is not currently supported on Windows 7 or Windows Server 2008 R2, we committed to provide security updates for the length of these ESU programs,” Microsoft says in a blogpost. “Therefore, after January 10, 2023, Microsoft 365 Apps running on Windows 7, Windows 8.1, or Windows Server 2008 R2 will stop receiving security updates. Additionally, new installations of Microsoft 365 Apps will be blocked on Windows 8.1 devices. We recommend that customers running these operating systems migrate to a supported OS before January 2023,” it said. SEE: These are the cybersecurity threats of tomorrow that you should be thinking about today Microsoft stopped providing free patches for Windows 7 on January 14, 2020, but it offered enterprise customers a few ways to continue getting security updates for the OS. The ESU updates for Windows 7 that end in January have cost customers between $25 to $200 per workstation. It also decided to continue to providing security updates for Microsoft 365 Apps on Windows 7 until January 2023, even though it officially didn’t support Microsoft 365 Apps on Windows 7. Though a little ambiguous, that policy meant that Microsoft didn’t guarantee performance and stability for these apps on devices running Windows 7, but it kept patching them on the legacy OS. Microsoft is strongly urging customers to migrate to Windows 10 or Windows 11 before January 2023. Microsoft notes that Microsoft 365 apps are supported under its Modern Lifecycle Policy, which governs subscription licenses versus non-subscription, versus versions of Office that are governed by the Fixed Lifecycle Policy. It’s a big deal for business when support ends for either Windows or Office products because Microsoft no longer provides security patches for products that are frequently targeted by hackers. It’s also a way for Microsoft to bump customers up to newer versions of its software. In June, support for its legacy Internet Explorer 11 ended on Windows 10. IE 11 wasn’t available on Windows 11, which uses Chromium-based Edge as the default. Microsoft will support IE Mode on Edge until at least 2029. “Please remember that using unsupported software may increase an organization’s exposure to security risks or impact its ability to meet compliance obligations,” Microsoft warns.