Outlook: Encrypt contents and attachments for outgoing messages
Let’s say you will send an private email message to your family about your bank information. For the sake of this message’s safety, you’d better to encrypt the email message in Microsoft Outlook. Here we will show you how to encrypt contents and attachments for outgoing email messages in Microsoft Outlook.
Encrypt contents and attachments for one message
Encrypt contents and attachments for all messages
Note: A valid digital ID is required on your computer if you want to encrypt contents and attachments for outgoing email messages in Microsoft Outlook.
Encrypt contents and attachments for one message
If you want to encrypt the content and attachments in a single email message, you can follow these steps:
Step 1: Create a new email message:
- In Outlook 2007, please click the File > New > Mail Message.
- In Outlook 2010 and 2013, please click the New Email button on the Home tab.
Step 2: In the Message window, please click the arrow button at the bottom-right corner in the More Options group on the Options tab. See screen shot:

Step 3: In the new dialog box, please click the Security Settings button in the Security section.

Step 4: In the Security Properties dialog box, please check the option of Encrypt message contents and attachments.

Step 5: Click the OK button and Close button to exit two dialog boxes.
Step 6: Compose your email message and click the Send button.
Note: Encrypting messages and attachments requires a valid Digital ID. If you have not added Digital ID on your computer, it will pop up an E-mail Security dialog box when you are clicking the Send button. See screen shot:

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Encrypt contents and attachments for all messages
If you need all email contents and their attachments encrypted automatically, please follow these steps:
Step 1: Open the Trust Center dialog box,
- In Outlook 2007, please click the Tools > Trust Center.
- In Outlook 2010 and 2013, please click the File > Options to open the Outlook Options dialog box, and then click the Trust Center > Trust Center Settings in the Outlook Options dialog box. See screen shot:

Step 2: In the Trust Center dialog box, click the E-mail Security in the left bar.
Step 3: Go to the Encrypted e-mail section, and check the option of Encrypt contents and attachments for outgoing messages.

Note: This method requires valid Digital ID in your Microsoft Outlook. Otherwise, it will warn you of getting invalid Digital ID or suggest you to get a Digital ID when you are clicking the Send button in composing email.
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