The basic way to attach an email to another email in Outlook

You cannot drag and drop an email into a new message the way you might attach a file. Instead, Outlook treats an email as a special kind of attachment that you add through the message menu. The process differs slightly depending on whether you use Outlook on the web, Outlook desktop for Windows, or Outlook for Mac — but the core idea is the same: you open a new message, find the attachment button, and select the email you want to include.

The most common reason to do this is to forward a conversation to someone who needs to see the original message exactly as it was, with all its formatting and headers intact. This is different from straightforward forwarding the email, because you can add your own message before or after the attached email, and the recipient sees both your note and the original message as a single file.

Key Takeaways

  • In Outlook desktop, you attach an email by opening a new message, clicking Attach File, navigating to your mailbox, and selecting the email you want to include.
  • In Outlook on the web, you use the paperclip icon and then choose "Email" from the menu that appears, rather than selecting a file from your computer.
  • An attached email appears as a .msg file in the recipient's inbox, which they can open to see the original message with all its details.
  • Forwarding an email is faster if you only want to pass it along, but attaching an email is better when you need to add context or combine multiple messages in one.

How to attach an email in Outlook desktop for Windows

Open the email you want to attach, or keep it visible in another window. Then open a new message by clicking File, then New, then Email Message — or straightforward press Ctrl+N. In the new message window, click the Attach File button in the ribbon at the top (it looks like a paperclip). A file browser window will open.

Instead of navigating to your Documents or Downloads folder, you need to navigate to your Outlook data folder. On most Windows computers, this is located at C:\Users\[Your Username]\AppData\Local\Microsoft\Outlook. Look for a file with a .pst extension (the default is usually named something like "Outlook.pst"). Double-click it to open it, and you will see folders that match your Outlook mailbox — Inbox, Sent Items, Drafts, and any custom folders you have created.

Navigate to the folder where the email you want to attach is stored, click on the email to select it, and click Insert. The email will now appear as an attachment in your new message, shown as a .msg file. You can add your own text above or below it, and send the message as normal.

How to attach an email in Outlook on the web

Open a new message by clicking Compose at the top left of your inbox. In the message window, look for the paperclip icon near the bottom of the compose area. Click it, and a small menu will appear with two options: "Browse this computer" and "Email". Click Email.

A panel will open on the right side showing your mailbox folders. Navigate to the folder containing the email you want to attach — usually your Inbox or a custom folder. Click on the email to select it, and it will be added to your message as an attachment. You can then type your own message and send it.

How to attach an email in Outlook for Mac

Open a new message by pressing Command+N or clicking File, then New, then Message. In the compose window, click the paperclip icon in the toolbar. A menu will appear; select "Attach Email" from the options shown.

A dialog box will open showing your mailbox folders. Navigate to the folder containing the email you want to attach and click on the email to select it. Click Insert, and the email will be added as a .msg attachment to your message. Type your own text and send as normal.

What happens when someone receives an attached email

The recipient will see your message with a .msg file attached — the same file format Outlook uses to store individual emails. They can double-click the attachment to open it in Outlook, or right-click it to save it to their computer. When they open it, they will see the original email exactly as it was, with all headers, formatting, and any attachments the original email contained.

If the recipient does not use Outlook, they may not be able to open a .msg file directly. Some email clients like Thunderbird can open .msg files, but others cannot. If you need to send an email to someone using a different email service, forwarding the message or copying and pasting the content may work better than attaching it.

When to attach an email instead of forwarding it

Forwarding is faster and simpler: you click Forward, add a note if you want, and send. But forwarding changes the appearance of the original message — it adds "FW:" to the subject line, and the recipient sees it as a forwarded message rather than the original.

Attach an email when you need to preserve the original message exactly as it was, or when you want to include multiple emails in a single message along with your own explanation. For example, if you are sending a manager a chain of emails between you and a vendor, attaching each email as a separate .msg file keeps them organized and makes it clear which messages are originals and which are your own notes.

Troubleshooting: Email does not appear in the file browser

If you navigate to your Outlook data folder and do not see any .pst files, your emails may be stored in a different location. In Outlook desktop, click File, then Account Settings, then Account Settings again. Click the Data Files tab, and you will see the location of your mailbox file. Navigate to that location instead.

If you are using Outlook on the web and the Email option does not appear in the attachment menu, your browser may not support it. Try using a different browser, or use the Outlook desktop process instead. If you are on a work or school account, your organization may have disabled the ability to attach emails for security reasons — contact your IT department to confirm.

Frequently Asked Questions

Can I attach multiple emails at once?

In Outlook desktop and Outlook for Mac, you can select multiple emails in your mailbox folder before clicking Insert, and they will all be added as separate attachments. In Outlook on the web, you typically attach one email at a time, but you can repeat the process to add more emails to the same message.

What if the email I want to attach is in a subfolder?

Navigate through your folder structure the same way you would in Windows File Explorer or Mac Finder. Click on the main folder, then double-click subfolders until you reach the one containing the email you want. The path works the same whether the email is in your Inbox or in a custom folder you created.

Does attaching an email include any attachments the original email had?

Yes. When you attach an email as a .msg file, the recipient receives the original email with all its attachments intact. They can open the .msg file and access any files that were originally attached to that email.

Why does my attached email show as a .msg file instead of the actual message?

That is how Outlook stores individual emails — as .msg files. The recipient needs to open the .msg file to read the message inside. This is normal and expected behavior; it is not an error.