When you start Windows 10 for the first time, there's a point in the setup process where you choose your level of privacy. The installer encourages you to use the express settings instead of customizing. But the express path will give Microsoft and Windows 10 more info about you than you may be comfortable sharing -- such as how you browse the web, what websites you visit, which apps you use and how frequently you use them -- so let's walk through how you can change that.
When you're done here, you should also look at our guide to Windows 10 security settings.
Privacy settings in the Control Panel
You access privacy settings through the Control Panel, which is now called Settings in Windows 10. The quickest way to get there is a keyboard shortcut: Windows-I. Another method is to tap the Windows key, which opens the Start menu, and then click the Settings button. You can also right-click this button and select Pin to Taskbar to create a shortcut for easier access later.
We'll focus on the second-to-last section in Settings, which is conveniently labeled Privacy. Since the Settings tool brings you back to wherever you last left off, you may not see the Privacy button if you've been fiddling around in Settings. If that's the case, click the back arrow in the upper left-hand corner of the window to go to the home window.
Before we start flipping switches, a word of warning: although you may be tempted to disable everything that reduces your privacy, doing so may impair or disable certain apps and interactions between apps. If you find that happening, you'll have to come back and re-enable things until the problem goes away, which could be time-consuming if you've changed a lot of settings. Unfortunately, the Privacy section does not have a button to restore default settings, so you'll have to track your changes on your own. We recommend taking screenshots of each section before you change anything.
Lastly, most categories in the Privacy section have a "learn more" link to a Microsoft webpage with more detail about what certain functions do. However, the level of disclosure and illumination varies.
The General pane
Clicking the Privacy button opens a window with two panes. On the left is a category list, and on the right are the settings for the category that you're looking at. In the General pane, there are four settings: advertising ID, SmartScreen, handwriting recognition, and language.
Advertising ID identifies your Web behavior to deliver targeted ads. It works like this: if you open the Windows 10 Travel app and also the Calendar app, Microsoft can use that info to show you ads for Expedia or Southwest Airlines, for example. That's assuming the app uses ads to begin with. You won't start seeing banner ads when you open the calculator, but Microsoft Edge (which replaces Internet Explorer as your default Web browser in Windows 10) may run these tailored ads when you go to Bing or Outlook.com.
Advertising ID communicates no personal information about you. It's a sort of beacon to deliver targeted ads showing something that you might want to buy. In theory, if the ads are more relevant to you, you're more likely to click them, which helps both the advertiser and the people selling the ad space, and maybe you, too, if you get a better shopping experience. But if you prefer to disable advertising ID, you can do so in the General pane. Note that disabling it does not block ads, only Microsoft's ability to target ads.
The SmartScreen filter is a layer that Microsoft Edge and Internet Explorer use to help protect you from dangerous or suspicious websites. The filter does this in two ways. One, it analyzes the website for questionable behaviors, like opening fake pop-up windows or redirecting you to other websites. Two, SmartScreen checks the Web address against a list Microsoft maintains of websites that are known to be fraudulent. You get the occasional false positive, meaning that a safe website is accidentally caught in the filter. But for the most part, SmartScreen is a helpful tool, so we recommend leaving it on.
The third setting helps improve handwriting recognition by sending Microsoft data about how you write. It doesn't send what you actually write. This setting will be grayed out if Windows 10 does not detect a stylus. Since it's not sending personally identifiable info, we don't see the harm in leaving it on.
The language setting helps websites detect which language you're using so they can deliver regional info, like maybe a Dow Jones stock ticker for users of US English or rugby scores for users of UK English. The setting also helps websites understand where its users are coming from, which can help them figure out what kind of content or user experience to create.
The Location pane
If you are using an administrator account, as you will be by default, then you will see the option to disable location info for all user accounts on that device. Below that is a toggle for the specific account that is currently logged in, which will be grayed out if location services are disabled for everyone. Location can be used to let Windows 10 apps display region-specific info like weather and sports scores, or to show you map locations and shopping choices in your area. If you disable this setting, you can still enter your location info manually -- it just won't be sent automatically.
Some apps will use your device's Bluetooth or Wi-Fi functions to determine your location even when your location setting is disabled. You can toggle that feature on and off in the Radios pane (in the list to the left). Bluetooth and Wi-Fi will still function, just without location info.
Camera and microphone
As you've probably guessed, these two sections have a toggle that disables your device's webcam and mic. You can also toggle for specific apps, including pre-installed apps designed by Microsoft and apps you have installed to replace them. If you purchased this device from a system builder like Dell, Acer, Toshiba, or Lenovo, they may have some pre-installed apps as well.
A Windows 10 app gets camera and microphone permissions by default if it wants it, regardless of how likely it is to use it, so we recommend checking these settings periodically if you're leaving your webcam enabled. Generally, you should only give webcam and mic access when you know you'll use them in that app, such as in Skype or HipChat. Note that disabling your webcam and mic in Settings may not prevent malware from secretly re-enabling it, and it won't have an effect on other operating systems that you may be dual-booting. You might want to put a piece of black tape over your webcam lens when you're not using it.
Speech, inking, and typing
The speech section is where you toggle Cortana's speech recognition, among other things. Cortana is like Apple's Siri, but it works on the desktop as well as on mobile devices. You can use speech recognition to dictate a text message to send to someone in your contacts list. Enabling the speech setting also improves handwriting recognition and search suggestions that are made as you type.
Contacts, Calendar, Messaging, and Radios
These next four sections work roughly the same: there's a toggle to turn the function off altogether, and a list of apps that you can toggle on an individual basis. If no apps are listed, none are asking for those permissions. If you're not using Cortana, and if you're using Gmail and Google Hangouts instead of a Windows 10 mail app or chat app, you can probably turn all of this off without much negative impact.
Windows 10 tells you a little about how the functions in the Other Devices section operate. But the company doesn't say much about what those functions will actually be used for; instead, it tells you to go to each app's website and look at the app's specific settings to figure that out. That's not encouraging, so most people will probably disable Other Devices until we get a better idea of how this stuff works. That doesn't seem like a bad idea.
Feedback & Diagnostics
Feedback & Diagnostics helps Microsoft improve how Windows 10 works. The feedback function controls a small notification bubble that sometimes pops up in the lower right-hand corner of the screen, asking you to rate a particular program or function in Windows 10. Unfortunately, Microsoft has tied diagnostic and usage data together, but you can still limit sharing to basic error info by going with the Basic option. The Enhanced setting sends Microsoft info about often and how long you use certain apps but also gives the company more diagnostic info for troubleshooting and for developing system updates.
The Full setting may send Microsoft personally identifiable information, such as the contents of a document you were working on when you experienced a crash. Microsoft states that it will not use this info "to identify, contact, or target advertising to you," but the potential privacy breach is pretty serious, so we recommend not using the Full setting, even though it sends a large amount of diagnostic info that helps Microsoft improve its apps and system updates. In fact, if this device is provided by your employer, the Full setting may be forbidden by company policy. If not, it arguably should be.
We've reached the last category of the Privacy section. Unlike the other categories, this one does not have a global toggle; each app must be toggled individually. Our list ran to 24 items, none of which seemed like they had to operate in the background to work effectively, so we disabled them all. Everyone's situation will be different. If you're a gamer, you may want to toggle the Xbox app on. If you use the Windows 10 calendar to keep track of events, then you'll probably want to let that run in the background as well.
Still have questions about Windows 10? We've answered a bunch (Part 1, Part 2), and you can read our full review. If you're not ready to commit to Windows 10, you might want to test it in a virtual machine instead (though the Insider preview is not currently available -- you'll need to test with Windows 10 Enterprise instead).