By default, Windows 11 only allows you to install applications from the official Microsoft Store or via traditional executable files (.exe or .msi). However, if you are a programmer writing your own software, or if you need to install specialised custom applications from outside the official store infrastructure (a process known as “sideloading”), Windows will block the installation.
To bypass these security restrictions and install unsigned apps (typically .msix or .appx packages), you must enable Developer Mode.
In this guide, you will learn how to safely enable Developer Mode in Windows 11 to facilitate app development and sideloading.
Important Security Warning
Developer Mode intentionally lowers the security threshold of your operating system. It allows the installation of applications that have not been vetted by Microsoft or digitally signed by a trusted certificate authority.
You should only enable Developer Mode if you are writing code yourself, or if you are installing a custom application provided by your employer or a highly trusted, verifiable source. Sideloading random apps from untrusted websites while in Developer Mode is a massive security risk and can expose your PC to malware.
Step 1: Open the Windows Settings
Developer Mode is a core system setting managed through the modern Windows interface.
- Click the Start button on your taskbar.
- Select the Settings gear icon (or press Windows Key + I on your keyboard).
Step 2: Navigate to Privacy and Security
Because Developer Mode alters how Windows handles untrusted software, it is located within the security section.
- In the left-hand sidebar of the Settings window, click on Privacy & security.
- Scroll down the main pane until you find the “Security” section.
- Click on For developers.
Step 3: Enable Developer Mode
You are now on the dedicated developer settings page.
- Look for the toggle switch directly to the right of the Developer Mode heading.
- Click the switch to turn it On.
- A stark warning dialog box will instantly appear, confirming that turning on this setting allows the installation of apps from any source, which could expose your device to security risks.
- Click Yes to acknowledge the risk and proceed.
Step 4: Configure Additional Settings (Optional)
Once Developer Mode is enabled, the switch will turn blue, and the page will instantly expand to reveal several advanced configuration options specifically designed for programmers. These include:
- Device Portal: Allows you to manage your PC remotely over a local network using a web browser (useful for testing on remote hardware).
- Device Discovery: Makes your PC visible to other devices on your local network for deploying apps via SSH or USB.
- File Explorer Tweaks: Quick toggles to show hidden files, file extensions, and full folder paths—vital for coding.
If you are simply enabling Developer Mode to sideload a single custom application, you do not need to alter any of these additional settings. You can now double-click your .appx or .msix file, and Windows 11 will install it without throwing a security error.
If you finish testing your code or sideloading your application, it is highly recommended to return to this settings page and toggle Developer Mode Off to restore the operating system’s default security posture.