It’s the end of support for Windows Server 2008.

This week’s Patch Tuesday marked the end of the line for Windows 7 and Windows Server 2008 (and 2008 R2). No more patches will be released for the two older operating systems unless you purchase an expensive extended service license.

On the Windows 7 front, Microsoft has done a good job of rolling out Windows 10 through its aggressive (perhaps too aggressive) upgrade program. According to StatCounter, Windows 10 now accounts for 65% of Windows’ global desktop market share, and Windows 7 has fallen to 27%.

But while Windows 7 got all the attention, Server 2008 actually has a bigger share of holdouts, and in some ways its end-of-life milestone is more important. At Inspire last July, a Microsoft executive said in an interview with cloud storage provider and Microsoft partner Carbonite that 60% of its current Windows Server installed base is running Server 2008, which amounts to 24 million instances.

“There’s a lot [of customers sticking with Server 2008]says analyst Tim Crawford of research and advisory firm AVOA. “You can categorize them into those who a) use WS2008-specific functions, and b) those who use a version of an application that is only compatible with WS2008. Upgrading is often easier said than done. especially if the app is a custom app with lots of tentacles.

Server 2008 is based on the Windows Vista code base, which should be the only reason to abandon it. But Windows Server 2016 and Windows Server 2019 are based on Windows 10, which means applications heavily dependent on the OS ecosystem can be difficult to move because the internal components are so different.

“I work with people who are still using Windows Server 2008. They understand the ramifications of EOL for support. But most of them are in a predicament where they are unable to move apps due to a number of reasons including app compatibility, location, etc. says Crawford.

For hard-to-move apps, he recommends isolating the system as much as possible to protect it and having a plan in place to do what’s necessary for the apps to get them ready for the move as quickly as possible.

Microsoft offers and recommends Azure migration, so that Server 2008 applications can run in an Azure instance while they are modernized to Server 2019 and then deployed on-premises.

Migration should be the overriding effort, because if you’re running Server 2008, you’re using hardware that’s at least eight years old and potentially 12 years old. It’s old in terms of technology, and if nothing else, the hardware will fail.

One of the headaches for administrators is that you cannot directly migrate Server 2008 to 2016 or 2019. You need to upgrade to Server 2012 as an intermediate step. So you’re better off biting the bullet and migrating apps to 2019 rather than spending time on two OS migrations.

Microsoft has provided resources for Server 2008 users, including a migration guide and help moving to Azure.