safedrop Messages - User Guide

Learn how to send and receive encrypted messages with file attachments.

Overview

safedrop Messages lets you send secure, encrypted communications with file attachments to anyone - whether they're in your organisation or external. All messages are end-to-end encrypted, meaning only you and your recipients can read them.

Sending a Message

Opening the Composer

1. Click Messages in the main menu
2. Click New Message
3. The message composer opens

Screenshot: The message composer interface

Composing Your Message

Required fields:

• Recipients - At least one email address
• Subject - A subject line for your message
• Message - The main content (supports Markdown formatting)

Optional settings:

• Expiry - How long the message remains accessible
• Attachments - Files to include with the message

Adding Recipients

1. Enter an email address in the recipients field
2. Press Enter on your keyboard or click the orange ' Add ' button
3. Repeat for additional recipients

Screenshot: Adding recipients to a message

Recipient Types

safedrop automatically detects recipient type based on their email address.

Adding Attachments

Uploading Files

1. Click the Attach Files button (or drag files to the composer)
2. Select files from your computer
3. Files upload and encrypt automatically

Screenshot: The file attachment area

File Limits

• Maximum file size: 10GB per file
• Multiple files can be attached
• All files are encrypted before upload

Upload Progress

For large files, you'll see:

• Upload progress bar
• Current status (preparing, encrypting, uploading)
• Upload speed and time remaining

Screenshot: File upload progress indicator

Message Settings

Retention Settings

Control how long your message remains accessible:

Screenshot: Message expiry configuration

Download Limits

Optionally limit how many times attachments can be downloaded:

• Leave blank for unlimited
• Set a number for download cap

Send Method

Choose how recipients receive access:

Sending the Message

Server Send

1. Complete all required fields
2. Click Send
3. Recipients receive an email with the secure link
4. Message is delivered!

Manual Send

1. Complete all required fields
2. Select Manual Send
3. Click Send
4. Copy the share link provided
5. Send the link to recipients yourself (via email, chat, etc.)

Screenshot: The manual send share link dialog

When to use Manual Send:

• When you want complete control over delivery
• For highly sensitive communications
• When recipients might have email filtering issues

Viewing Sent Messages

Message List

1. Go to Messages
2. See all your sent messages
3. View status and recipient count

Screenshot: The sent messages list

Message Status

Message Details

Click a message to view:

• Full message content
• List of recipients and their access status
• Attached files
• Activity log (who viewed/downloaded)

Viewing Message Activity

Activity Log

Each message tracks:

• When recipients viewed the message
• When attachments were downloaded${color}[#ea0606](

Download counts per file)

Screenshot: The message activity log

Recipient Status

Receiving Messages

Email Notification

When someone sends you a safedrop message:

1. You receive an email notification
2. Click the link in the email
3. You're taken to the message viewer

Accessing the Message

For safedrop users:

1. Log in if prompted
2. Your encryption keys automatically decrypt the message
3. View the content and download files

For external recipients:

1. Click the link in your email
2. Enter the one-time password (OTP) sent to you
3. View the message content
4. Download any attachments

Screenshot: The OTP entry screen for external recipients

Downloading Attachments

1. View the message
2. Click Download next to any file
3. File is decrypted and saved to your device

For large files, you'll see download progress.

Message Security

End-to-End Encryption

Every message is encrypted with:

• Message Encryption Key (MEK) - Unique key for the message
• File Encryption Keys (FEK) - Unique key for each attachment
• Recipient Wrapping - (MEK) is wrapped for each recipient

How It Works

1. Your browser generates encryption keys
2. Message content is encrypted locally
3. Encrypted content is uploaded to SafeDrop
4. Recipients decrypt using their keys (or OTP-derived keys)

SafeDrop servers never see your unencrypted content.

Share Token Security

For external recipients:

• A share token is included in the URL (after #)
• This token is never sent to the server
• Combined with OTP to derive decryption key

Managing Messages

Archiving Messages

1. Find the message in your list
2. Click the box on the left of message, this selects the message
3. At the bottom of your screen the ' Archive ' & ' Delete' options are now available to select
4. Select Archive

Archived messages are preserved but hidden from the main list.

Deleting Messages

1. Find the message
2. Click the box on the left of message, this selects the message
3. At the bottom of your screen the ' Archive ' & ' Delete' options are now available to select
4. Select Delete
5. Confirm deletion

Warning: Deleted messages cannot be recovered. Recipients lose access immediately.

Extending Expiry

Before a message expires:

1. Open the message
2. Click Extend
3. Choose new expiry date
4. Confirm

Viewing Message Activity

Activity Log

Each message tracks:

• When recipients viewed the message
• When attachments were downloaded${color}[#ea0606](

Download counts per file)

Screenshot: The message activity log

Recipient Status

Troubleshooting

Recipient Not Receiving Email

1. Ask them to check spam/junk folder
2. Verify the email address is correct
3. Check if their email blocks safedrop
4. Use Manual Send and share link directly

OTP Not Working

1. Ensure OTP is entered exactly (case-sensitive)
2. Request a new OTP if expired
3. Check spam folder for OTP email
4. Try on a different device/browser

Cannot Decrypt Message

1. Ensure you're logged into the correct account
2. Try logging out and back in
3. If keys are corrupted, use recovery phrase
4. Contact sender to resend if needed

Large File Taking Long Time

1. This is normal for large files
2. Keep browser tab open during download
3. Use wired connection if possible
4. Check available disk space

Best Practices

Composing Messages

1. Use clear titles - Helps recipients and your own tracking
2. Set appropriate expiry - Don't leave sensitive content accessible forever
3. Consider file size - Large files take time for recipients to download
4. Double-check recipients - Verify email addresses before sending

Security

1. Use Manual Send for highly sensitive content - Adds extra control
2. Set download limits - For sensitive attachments
3. Verify recipient identity - Especially for first-time external contacts
4. Delete when done - Remove messages that are no longer needed

External Recipients

1. Inform them about OTP - Let them know to check email
2. Provide context - They may not be familiar with safedrop
3. Set reasonable expiry - Give them time to access
4. Follow up - Ensure they received the message

Need more help? Contact your organisation's safedrop administrator.

Updated on: 23/01/2026