Windows 11/10 に BitLocker をインストールする方法：完全セットアップガイド
If you are searching for a ビットロッカーのインストール, the first thing to know is that you normally do not need to download BitLocker separately. BitLocker is built into supported editions of Windows 11 and Windows 10, including Pro, Enterprise, and Education. In most cases, “installing BitLocker” simply means turning on BitLocker Drive Encryption and completing the initial setup.
This guide explains how to install or enable BitLocker on Windows 11 and Windows 10, check whether your PC supports it, encrypt an internal or external drive, and safely back up your recovery key. We will also explain what Windows Home users can do and why BitLocker may sometimes appear to turn itself on automatically.
Before enabling encryption, make sure you have a safe place to store your recovery key. If you later have trouble locating an existing key, see our ビットロッカーのリカバリ guide for available recovery options.
目次
Quick Answer: Do You Need to Install BitLocker?
For most Windows 11 and Windows 10 PCs, you do not download or install BitLocker as a separate application. If you use Windows Pro, Enterprise, or Education, BitLocker Drive Encryption is already included with Windows.
To start using it:
- 検索 BitLockerの管理 「スタート」メニューから。.
- オープン BitLocker ドライブ暗号化.
- Find the drive you want to protect.
- クリック BitLockerをオンにする.
- Choose where to back up your recovery key.
- Select an encryption option and start encryption.
Windows Home users may have デバイスの暗号化 instead of the full BitLocker management interface. Windows Server is different: the BitLocker feature may need to be installed before it can be enabled.
What Does “BitLocker Install” Actually Mean?
BitLocker is Microsoft’s built-in drive encryption technology. On supported Windows desktop editions, there is usually no BitLocker installer to download and no separate application to install.
人々が検索するとき ビットロッカーのインストール, they are usually trying to do one of three things:
- Turn on BitLocker on Windows 11 or Windows 10.
- Find BitLocker on a PC where the option appears to be missing.
- Install the BitLocker feature on Windows Server.
These situations require different steps, so first check which edition of Windows you are using.
Which Windows Editions Include BitLocker?
| Windows edition | BitLocker availability |
|---|---|
| Windows 11 Pro | Full BitLocker Drive Encryption |
| Windows 11 Enterprise | Full BitLocker Drive Encryption |
| Windows 11 Education | Full BitLocker Drive Encryption |
| Windows 10 Pro | Full BitLocker Drive Encryption |
| Windows 10 Enterprise | Full BitLocker Drive Encryption |
| Windows 10 教育 | Full BitLocker Drive Encryption |
| Windows Home | May provide Device Encryption on supported hardware |
| Windowsサーバー | BitLocker feature may need to be installed |
To check your Windows edition, go to Settings > System > About and look under Windows specifications.
How to Install BitLocker on Windows 11/10
Because BitLocker is already included with supported editions of Windows, the setup process is mainly about enabling encryption.
Step 1: Check Your Windows Edition
プレス ウィンドウズ＋I to open Settings, then go to:
System > About
Check the Windows edition under Windows specifications.
If you have Windows Pro, Enterprise, or Education, you can continue with the full BitLocker setup.
Step 2: Open Manage BitLocker
Open the Start menu and search for:
BitLockerの管理
選択 BitLocker ドライブ暗号化 結果より.
You can also open Control Panel and go to:
システムとセキュリティ > BitLockerドライブ暗号化
Step 3: Select the Drive
Locate the operating system drive or data drive you want to encrypt and click:
BitLockerをオンにする
Windows will begin preparing the drive for encryption.
Step 4: Back Up and Protect Your BitLocker Recovery Key
Before encryption begins, Windows asks you to back up your BitLockerリカバリーキー. This 48-digit key can restore access to the drive if BitLocker cannot unlock it normally after certain hardware, firmware, or security changes.
Depending on your Windows configuration, you may be able to save the recovery key to your マイクロソフトアカウント, a USB flash drive, a separate file, or a printed copy.
For better protection:
- Keep at least one recovery-key backup separate from the encrypted PC.
- Do not save the only copy on the drive you are encrypting.
- If you use a USB drive or printed copy, store it separately from the computer.
- Make sure you can actually access your Microsoft account or other backup location before continuing.
Once the recovery key is safely backed up, click 次のページ to continue the BitLocker setup.
Step 5: Choose How Much of the Drive to Encrypt
Windows normally provides two options:
Encrypt used disk space only
Best for a new PC or a relatively empty drive because the initial encryption can finish more quickly.
Encrypt the entire drive
More appropriate for a drive that has already contained files.
Select the option that fits your situation and continue.
Step 6: Select an Encryption Mode
Windows may ask you to choose between a newer encryption mode and a compatible mode.
Use the newer mode for drives that will remain with modern Windows systems. Consider the compatible mode for removable drives that may need to work with older Windows versions.
Step 7: Start BitLocker Encryption
Follow the remaining prompts and start the encryption process.
For an operating system drive, Windows may perform a BitLocker system check and ask you to restart the PC before encryption begins.
After Windows restarts, BitLocker will continue encrypting the drive in the background.
Can You Install BitLocker on Windows 11 Home?
Windows 11 Home does not include the same full BitLocker Drive Encryption management tools available in Pro, Enterprise, and Education editions. However, many compatible Windows Home devices support デバイスの暗号化, which also uses Windows drive-encryption technology to protect stored data.
確認する：
- オープン 設定.
- こちらへ プライバシーとセキュリティ.
- 選択 デバイスの暗号化.
If Device Encryption is available, you can turn it on from this page.
If the option does not appear, your device may not meet the required hardware or configuration conditions. If you specifically need the full BitLocker management features, upgrading to a supported Windows edition is the standard option rather than downloading a third-party “BitLocker installer.”
How to Install BitLocker on Windows Server
Windows Server works differently from Windows 11 and Windows 10. On supported Windows Server editions, the BitLocker feature may need to be installed before you can use it.
Install BitLocker with Server Manager
オープン Server Manager and select:
Manage > Add Roles and Features
Continue through the wizard until you reach 特徴, 選択 BitLocker ドライブ暗号化, and complete the installation.
A restart may be required.
Install BitLocker with PowerShell
Administrators can also install the BitLocker feature with PowerShell:
Install-WindowsFeature BitLocker -IncludeAllSubFeature -IncludeManagementTools -Restart
After the server restarts, you can configure BitLocker protection for the required drives.
Note: Windows Server installation is different from normal Windows 11/10 BitLocker setup. Desktop users generally only need to enable the BitLocker feature already included with Windows.
How to Check Whether BitLocker Is Working
戻る BitLockerの管理 and check the status beside the drive.
Advanced users can also open Command Prompt as administrator and run:
manage-bde -ステータス
This displays the encryption status and BitLocker protection information for available drives.
For more command-line options, see our BitLocker CMD guide.
BitLocker Is Missing: Why Can’t I Find It?
If you search Windows for BitLocker but cannot find the expected controls, check these common causes first.
| 問題 | チェックポイント |
|---|---|
| You use Windows Home | Look for Device Encryption instead of the full BitLocker interface |
| Device Encryption is missing | Check whether your hardware and Windows configuration support it |
| BitLocker is managed by your organization | Contact your system administrator before changing encryption settings |
| TPM-related options are unavailable | Check TPM status in Windows Security or your PC’s UEFI/BIOS |
| BitLocker controls appear but encryption will not start | Check the error message before changing TPM, policy, or disk settings |
Avoid downloading software advertised as a standalone “BitLocker installer.” On supported Windows desktop editions, BitLocker is already part of Windows.
What If You Cannot Find Your BitLocker Recovery Key?
Saving the recovery key is one of the most important parts of BitLocker setup. Before troubleshooting with third-party tools, first check the locations where the key may already have been backed up, such as your Microsoft account, a work or school account, a USB drive, a printed copy, or your organization’s key-management system.
If you need to search a Windows system for existing BitLocker recovery key information, Magic Recovery Key can help locate supported recovery-key records along with other Windows and software credentials.
Magic Recovery Key does not crack BitLocker encryption or bypass BitLocker security. Its role is to help retrieve recovery-key information that already exists in supported system or storage locations.
手順はとても簡単です：
1. ソフトウェアをダウンロード＆インストール
Magic Recovery Keyの公式ウェブサイトにアクセスしてソフトウェアをダウンロードし、インストールしてください。インストールは素早く簡単で、数分以内にリカバリースキャンを開始できます。.
Windows 7/8/10/11およびWindows Serverをサポート
2.BitLocker Recovery Key “を起動し、選択します。”
メイン・インターフェースから “「BitLockerリカバリーキー” オプションを選択します。このモジュールは、システムに保存されている BitLocker 認証情報を徹底的にスキャンするように設計されています。.
3.スキャンを開始する
をクリックする。 “検索” ボタンをクリックしてスキャンプロセスを開始します。このソフトウェアは、現在の Windows インストール、接続されているドライブ、システム・ファイル、および構成データを自動的に分析し、BitLocker 復元キーがないかどうかを調べます。このプロセスは完全に自動化されており、技術的な専門知識は必要ありません。.
4.キーの取得と使用
BitLocker 回復キーがシステムで見つかった場合、, Magic Recovery Key をクリックすると、画面にはっきりと表示されます。その後 48桁のリカバリーキー それを使って BitLockerで暗号化されたドライブのロックを解除します。, Windowsの回復プロンプトを使うか manage-bdeコマンドライン ツールを使用する。.
Why Did BitLocker Appear to Install Itself?
If you never manually turned on BitLocker but later discovered that your drive was encrypted, Windows may have enabled デバイスの暗号化 automatically during device setup.
On compatible devices, signing in with a Microsoft account or a work or school account can cause Device Encryption to turn on and associate a recovery key with that account.
In managed business environments, administrators may also configure encryption through organizational security policies.
This does not mean Windows secretly downloaded a separate BitLocker application. BitLocker and Device Encryption are built into Windows, and encryption can become active when the required Windows edition, hardware, account, and security settings are present.
If BitLocker suddenly asks for a recovery key, first check your Microsoft account or your organization’s recovery-key records before attempting other recovery methods.
まとめ
A ビットロッカーのインストール on Windows 11 or Windows 10 usually does not require downloading any additional software. On supported Windows editions, BitLocker is already built in—you simply need to open BitLocker Drive Encryption, turn it on for the required drive, save the recovery key, and complete the encryption setup.
Windows Home users should check whether デバイスの暗号化 is available, while Windows Server administrators may need to install the BitLocker feature before configuring encryption.
Most importantly, save your recovery key somewhere separate from the encrypted drive. If the key later becomes difficult to locate, start with your Microsoft account or organization’s recovery records. You can also review our ビットロッカーのリカバリ guide or use Magic Recovery Key to search supported locations for existing recovery-key information.
Windows 7/8/10/11およびWindows Serverをサポート
BitLockerのインストールに関するFAQ
Do I need to install BitLocker on Windows 11?
Can I download BitLocker from Microsoft?
How do I install BitLocker on Windows 10?
Can I install BitLocker on Windows 11 Home?
Why is BitLocker missing from my PC?
BitLockerは自動的にインストールされますか？
Do I need a TPM to use BitLocker?
3. BitLocker回復キーとは何ですか？また、紛失した場合に見つける方法は何ですか？
