How to create or edit your Outlook signature for email messages. Include your signature, text, images, electronic business card, and logo.

Certificate authority (CA) A certificate authority is an entity similar to a notary public. It issues digital certificates, signs certificates to verify their validity and tracks which certificates have been revoked or have expired. Top of Page Digital signature assurances The following terms and definitions show what assurances are provided by digital signatures. Authenticity The signer is ...

Want to add a padlock to your email messages? You can use encryption and digital signatures in new Outlook, classic Outlook, and Outlook on the web for work or school accounts to increase the security of messages. Encrypting an email message in Outlook means it's converted from readable plain text into scrambled cipher text. Only the recipient who has the private key that matches the public ...

If you're using the Microsoft Outlook app or Outlook.com, and if you and your recipients are all on Microsoft Exchange or Microsoft 365 and in the same organization, you can recall or replace an email message that you sent.

Windows セキュア ブート証明書の有効期限 重要: ほとんどの Windows デバイスで使用されているセキュア ブート証明書は、2026 年 6 月から有効期限切れになる予定です。 これは、特定の個人用デバイスとビジネス デバイスが時間内に更新されていない場合に安全に起動する機能に影響する可能性が ...

This update enables dynamic status reporting for Secure Boot states in the Windows Security App (Settings > Update & Security > Windows Security). Learn more about the status alerts via badges and notifications.

The default authentication method is to use the free Microsoft Authenticator app. If you have it installed on your mobile device, select Next and follow the prompts to add this account.

Learn how to sign in and create app passwords for Microsoft apps and devices that don't support two-step verification.

Go to Home > Editing > Replace. Enter the word or phrase you want to replace in Find what. Enter your new text in Replace with. Choose Replace All to change all occurrences of the word or phrase. Or, select Find Next until you find the one you want to update, and then choose Replace. To specify only upper or lowercase in your search, select More > Match case. There are several other ways to ...

To access your privacy settings, open any Office application, select the app menu > Preferences > Privacy. This will open the Account Privacy settings dialog box where you can select your privacy options.