Simply compose a new email as normal and attach your file. Any attachment over 20MB will automatically be managed as a large file. You will notice the attachment icon is now an M indicating it will be sent using the Mimecast large file send functionality. The attachment size is now also significantly smaller but don't worry, the file will be sent as normal. Continue to add attachments as desired.



  1. Create a Message.
  2. Click on the Mimecast tab.
  3. Click on the Attach Large Filesicon.
  4. Select the Filesyou want to attach.
    Note: The selected files are attached to the message with a notification that they will be sent via Large File Send. The file extensions are changed to .LFS, which means you cannot preview them. If you want to ensure you're sending the correct files, check them before selecting them.
  5. Click the Send button.
  6. Amend the Large File Send options as required:

 

The options available are explained below.


Expire access to the files after.

Choose a date after which you no longer want the recipient to have access to the file/s.


Notify me when the files are accessed.

You will receive a notification via email when the recipient accesses the large file.


Send me a link to the files.

You will receive an email including a link to the file itself, this can be useful in case you delete it from your computer and need to access it again.


Invite recipients to send me large files.

If you are collaborating on a document or presentation, you can invite the recipient to send the file back to you once they have completed their review or added content. They won’t need to worry about the file size or use less secure third party systems to send it.


Use an access key for additional file security.

For more sensitive and confidential content, we recommend you always use this option, especially for external recipients. The recipient will be prompted to request a security key, which will be delivered via email, before being able to access the file. Keys are generated automatically so you won't have to provide them.


You will see a notification when the file has been uploaded and sent. 

Remember to not close Outlook or your computer until you see this.