Joining the Windows Insider Program
After registering at https://insider.windows.com, you're ready to configure a Windows 10 device to receive Insider Preview builds. Go to Settings → Update & Security → Windows Insider Program and click Get Started.
The first step is to link your PC to the registered Insider account. In most cases, the Microsoft account you use to sign in to Windows 10 is the best choice here. Then walk through the wizard's steps to configure your Insider settings.
If you're willing to accept the risks of installing preview builds in exchange for the opportunity to influence the direction of Windows, click Get Started and link an account that you've registered with the Windows Insider Program.
After that step is complete, you need to choose one of three Insider Preview channels. Over time, these channels have evolved, with Fast and Slow rings as well as an occasional (but limited) option for Insiders in the Fast ring to "skip ahead" a full version. As of mid-2020, those options are replaced by three channels whose names and general contours match those used for other Microsoft software and services, including Microsoft Edge, Microsoft 365, and Microsoft Teams test releases.
- Dev Channel
Preview builds go to this group of Insiders first. The benefit of being first to see a new feature is balanced by the risk of being the first to experience a new bug. You can report those bugs using the Feedback Hub. Microsoft recommends this channel for "highly technical users." - Beta Channel
Devices configured for this "early adopter" channel receive preview builds after they've had a chance to be thoroughly tested by the Dev channel. These builds are aligned to a specific upcoming release and are likely to be more stable and reliable because they incorporate fixes based on feedback from testers in the Dev channel. - Release Preview Channel
This is the most conservative channel of all, offering new builds near the end of the development cycle for a feature update. Insiders who choose this channel also receive advanced quality updates and have early access to certain key features. These builds are fully supported. Microsoft recommends this channel for IT pros who want to preview and validate upcoming releases without a major risk of instability.
Before you can complete the configuration process, you must click through two bold and very stern warnings, which list the risks we discussed earlier. After a restart, you're ready to begin receiving new builds. The current Insider Preview release that matches your preferences will download and install automatically, just like any feature update.
After configuring a device to receive Insider Preview builds, you should see some new options in the Windows Insider Program section in Settings → Update & Security. There, you can change your Insider settings by changing the channel, which indirectly changes the pace at which you receive new builds. To use a different account with a specific device, register that account with the Windows Insider Program. Then click the account card at the bottom of that Settings page and use the Change or Unlink buttons.
Insider Preview builds arrive via Windows Update, as normal. After installing an Insider Preview build, you can see a few changes. For starters, a watermark appears in the lower-right corner of the screen, above the clock in the notification area, with the words "Evaluation copy" and the Insider Preview build number. (This watermark disappears for some builds that are released near the end of a development cycle, as Microsoft prepares the final preview builds for the official release.)
In addition, on a PC configured to receive Insider Preview builds, some privacy settings can't be adjusted. If you go to Settings → Privacy → Diagnostics & Feedback, for example, you'll find that the Feedback Frequency options are set to the default levels, and a message on that page discloses that the Windows Insider Program has taken control of those options.
Those options return to normal when you change the configuration of a device so that it no longer receives Insider Preview builds and is back on the Semi-Annual Channel.
Making sense of Windows code names
Each new Windows 10 feature update has its own code name, which you can use to track that version as it works its way through the development process, a process called "flighting." The initial release of Windows 10, in July 2015, was code-named Threshold, and the second release, version 1511, was identified as Threshold 2. The Anniversary Update, version 1607, was code-named Redstone, and subsequent feature updates were code-named Redstone 2, Redstone 3, Redstone 4, and Redstone 5. For a brief period in 2019, Insider builds used the code name Vibranium.
Those code names are mostly useful to those who have enrolled in the Windows Insider Program and are actively testing upcoming versions. The first public preview release from the Redstone 5 flight arrived for those in the Skip Ahead group well before version 1803 (the formal name of what had previously been Redstone 4) became publicly available. The designation "rs" in the file name for a download of a preview build is a giveaway to informed observers that the new build belongs to the Redstone development cycle.
When running an Insider Preview build, you can suspend delivery of new builds for up to seven days. Go to Settings → Update & Security → Windows Update, click Advanced Options, and then click Pause Updates For 7 Days. You might choose to make this change if you're in the midst of a big project and don't want your work to be interrupted by a large download that could take an hour or more to install. You might also choose to stop updates temporarily if you're traveling. As a member of the Windows Insider Program, however, that delay is limited to a week. (For a device in the public Semi-Annual Channel, you can use the same option to pause updates for up to 35 days.)
As long as your PC is enrolled in the Windows Insider Program, you will continue to receive new builds. When the development cycle for one release ends, the next one begins without interruption. To configure your PC so that you stop receiving Insider builds when the next public release of Windows 10 is installed, go back to Settings → Update & Security → Windows Insider Program and turn on the Stop Getting Preview Builds switch at the bottom of the page.
Of course, setting that option has no effect on your current installation. As we noted earlier, the only way to leave the Windows Insider Program in the middle of a development cycle is to install a clean copy of a released version of Windows 10.