How To Forward As Attachment: The Complete Guide To Email Archiving

Forwarding an email as an attachment preserves the original headers, metadata, formatting, and embedded files without altering the message body, ensuring seamless forensic integrity and clean handoffs. This method is the industry standard for compliance auditing, technical support escalation, and malicious phishing reporting.

Pre-Operation & Equipment Checklist

Proper execution of email management tasks requires understanding the specific environment and mail client constraints. Unlike standard inline forwarding, which strips authentication headers and nests quotes recursively, forwarding as an attachment packages the target message as a standalone .eml or .msg file.

• Essential Software and Access: Access to a primary desktop or web-based email client (Microsoft Outlook, Apple Mail, Mozilla Thunderbird, Gmail, or webmail interfaces).
• Mandatory Prerequisite Knowledge: Familiarity with MIME (Multipurpose Internet Mail Extensions) standards, basic file types (.eml for standard RFC 5322 compliance, .msg for proprietary Outlook formatting), and security protocols regarding untrusted payloads.
• Time and Scope Benchmarks: Execution takes under sixty seconds per message, with batch operations scalable via native filtering rules and script automation.

Step-by-Step Procedure for Forwarding as an Attachment

Step 1: Access Your Primary Mail Client and Locate the Target Message

Open your desktop client, mobile application, or web browser and navigate to the inbox or archive folder containing the message you wish to transfer. Do not open the message body if it contains potentially active web beacons or malicious scripts; selecting it in the preview pane or highlight view is sufficient for the export process.

Pro-Tip: If you are using Microsoft Outlook on a Windows desktop, you can use the keyboard shortcut Ctrl + Alt + F to instantly convert any selected message into an attachment within a new compose window.

Step 2: Initiate the Attachment Command Based on Client Architecture

Depending on your specific mail infrastructure, the command to package the email changes. In Microsoft Outlook desktop applications, click the "Home" tab in the ribbon menu, locate the "Respond" group, and select "Forward as Attachment." In Apple Mail, navigate to the top menu bar, select "Message," and choose "Forward As Attachment." For web-based clients lacking a dedicated button, drag and drop the target message directly into an open compose window, or use the "Download message" option to save the .eml file locally before dragging it into your new outgoing message.

Warning: Avoid taking screenshots of emails for forwarding purposes. Screenshots strip clickable links, lose metadata, break text searchability, and fail compliance auditing standards.

Step 3: Verify Payload Integrity and Compose the Transmission

Examine the newly generated draft window to confirm that the attachment icon displays the original subject line with a .eml or .msg extension. Enter your recipient addresses in the To, Cc, and Bcc fields, and write a clear explanatory message in the body section providing context on why the attachment is being shared. Ensure the cumulative file size of all attached messages remains below your mail server limits, typically 25MB to 50MB depending on enterprise configurations.

Step 4: Execute Final Outbound Security Checks and Send

Review the recipient list for accidental inclusion of sensitive internal domains, and verify that no unintended personal data resides in your added response text. Click the send button to dispatch the package across the Simple Mail Transfer Protocol (SMTP) pipeline, ensuring the receiving party gets an untouched, cryptographically intact digital artifact.

Email Forwarding Formats and Client Compatibility Matrix

Common Mail Transfer Failures and Field Fixes

• Root Cause: The webmail interface lacks a visible "Forward as Attachment" button.
  
  
  • Actionable Fix: Open the message, click the three-dot menu icon in the upper-right corner of the email pane, and select "Download message" or "Show original." Save the resulting file to your local drive and attach it manually to your new outgoing draft.
• Root Cause: The recipient reports that the attachment appears as a generic winmail.dat file.
  
  
  • Actionable Fix: This occurs when sending proprietary Outlook .msg files to non-Microsoft clients (like Apple Mail or Thunderbird). Configure your Outlook outbound mail settings to send messages in plain text or HTML format rather than Transport Neutral Encapsulation Format (TNEF).
• Root Cause: Attachment size exceeds server threshold limits during bulk forwarding operations.
  
  
  • Actionable Fix: Compress multiple .eml files into a single .zip archive before attaching, or leverage a secure enterprise file-sharing link rather than direct SMTP attachment transfer.

Frequently Asked Questions

What is the difference between standard forwarding and forwarding as an attachment?

Standard forwarding copies the text of an email into a new message body, stripping out original transport headers, server hops, and hidden metadata while allowing the recipient to edit the content. Forwarding as an attachment wraps the entire original email file into your new message, preserving every cryptographic signature, routing header, and embedded asset in its exact original state.

Why should I forward phishing emails as attachments?

Forwarding a malicious email as an attachment preserves the full SMTP header data, which cybersecurity analysts and automated threat intelligence systems require to trace the true origin, routing path, and sender infrastructure of the attack. Inline forwarding destroys this telemetry, making proper incident investigation significantly harder.

Can I forward multiple emails as a single attachment?

Yes, most desktop clients like Outlook and Thunderbird allow you to highlight multiple emails simultaneously using Shift-click or Ctrl-click, and then apply the "Forward as Attachment" command to package all selected messages into a single outgoing draft. For webmail clients, you may need to download the messages individually or compress them into a .zip file.

Does forwarding an email as an attachment compromise my privacy?

Forwarding an email as an attachment does not expose your private contact list, but it does include your email address in the delivery path headers of the newly generated message. If the original email contained sensitive internal routing information or hidden metadata, the recipient will be able to inspect those technical details upon opening the attached file.

Master email management and compliance workflows by standardizing your forwarding protocols across all enterprise communication channels today.