One of Windows 10's best-kept secrets is the Long Term Servicing Branch (LTSB) edition. Its biggest selling point is its apparent simplicity. Once installed, you get the usual security and reliability fixes each month, but none of the feature updates, which are equivalent to full upgrades.

For administrators who aren't yet comfortable with the "Windows-as-a-service" model ushered in by Windows 10, it sounds like a familiar servicing model. But there are some gotchas you need to know about.

Let's start with a few facts about what LTSB is and how it works.

SEE: Securing Windows policy

About LTSB

LTSB is a licensing option for Windows 10 Enterprise and is available only for customers with a Volume License agreement.

Each LTSB release receives standard monthly security and reliability updates for an extended 10-year support period. No new features are added over its servicing lifetime.

When you install Windows 10 Enterprise LTSB, you'll notice some missing pieces. There's no Windows Store client, nor will you find Microsoft Edge or Cortana--both of which are system apps that can't be removed from other Windows 10 editions. Because the LTSB releases have no Store client, you don't get any of the preinstalled universal apps, such as Mail/Calendar, OneNote, Photos, Groove Music, the MSN Weather/News/Sports/Money apps, and the Camera and Alarms & Clock apps.

The resulting installation is remarkably clean. Compare the Start menu in Figure A, for example, to what you see on a new PC running a retail or OEM release of Windows 10.

Figure A

Figure A

Most Windows 10 users are about to receive the third major release of Windows 10. The first, released in summer 2015, was version 1507, build 10240; that was followed by version 1511 last November and then by the Anniversary Update, version 1607. Each of those updates includes major new features and a potentially disruptive upgrade process.

But the only LTSB version currently available is that original release of Windows 10 from last year, build 10240. If you check in Windows 10 Settings, you can see its edition information reported as Windows 10 Enterprise 2015 LTSB, as shown in Figure B.

Figure B

Figure B

Each month, LTSB machines get security patches--but they will never receive any newer features unless you specifically install a new image.

If that sounds like something you're interested in, ask yourself the following questions.

1: Do I have any workloads that are appropriate for LTSB?

In creating this branch of Windows, Microsoft's goal was to serve the needs of what it calls "specialized devices." These machines typically run one or two mission-critical applications, where avoiding downtime and instability is a primary goal. It's not intended for workstations that do general-purpose productivity tasks.

2: Are my update expectations realistic?

If you're thinking of LTSB as a way to avoid the headaches of Windows 10's servicing model, you're going to be disappointed.

For monthly updates, Windows 10 LTSB follows the same servicing model as other branches. All of these security and reliability updates are cumulative and must be installed in their entirety. Each cumulative update supersedes the previous one and contains all security and non-security fixes released up to that point.

If you're hoping to be able to pick and choose individual updates to install, that's not an option. You can delay installing cumulative updates for several weeks using Group Policy settings, but that option is available for all editions, not just LTSB.

In terms of updating, the only difference with LTSB is that you won't see feature updates.

3: Am I sure this is the license I want?

You can upgrade the current Windows 10 Enterprise 2015 LTSB edition to a newer LTSB release, when it's available. You can also switch to a different branch of Windows 10 Enterprise edition. But in either case, you'll need to pay for a new license or purchase Software Assurance.

For a single-purpose machine that you're confident will run a mission-critical application properly on that release, that might be exactly what you want. But for any system that also performs general-purpose computing tasks, there are better options available.

4: Which options are available for general purpose PCs?

If your goal is to minimize the disruption of frequent feature updates, the Current Branch for Business is probably your best bet.

When Microsoft releases a new Windows 10 update, such as the Anniversary Update (version 1607), the release goes first to the Current Branch, made up of consumers and small businesses running Windows 10 with its default settings. Enterprises can use the Windows Update for Business settings to specify that they want machines to be on the Current Branch for Business instead. (I'll have more on Windows Update for Business in my next column.)

Each Current Branch for Business release lags the Current Branch by at least four months. Version 1511, for example, went to most Windows 10 users in November 2015, but it wasn't declared ready for the Current Branch for Business until April 2016.

And if you're really conservative, you can specify that you want to defer those upgrades as well. Using Windows Update for Business, you can wait up to eight months after the release of a Current Branch for Business build before you deploy it.

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