How does the "postpone delivery" function in Oulook work?

In Outlook 365, for example, you have the function to postpone the delivery. You can specify a specific date and time so your message and attachment will be sent at that time. We are happy to explain this function.

Will my files remain available for 14 days after the mail has been sent? 

No, from the moment the e-mail is in 'Outbox', the files have already been uploaded to the server. You can see that in the Upload Manager at the bottom of the taskbar. The link is already generated and the mail is ready to send. Although you have chosen to postpone the e-mail, the link will be available for 14 days from the time of upload. 

So keep in mind when you postpone an email with attachment, you don’t do this for more than 7 days. The recipient has 7 days to open the link before it expires.