Email account deleted?

I received an email from (bit angry) friend today and when I replied (after around two hours), I received postmaster failure notification

Reporting-MTA: dns;SNT004-OMC2S34.hotmail.com
Arrival-Date: Mon, 20 Jun 2016 00:19:03 -0700
Final-Recipient: rfc822;***********@gmail.com
Action: failed
Status: 5.5.0
Diagnostic-Code: smtp;550-5.1.1 The email account that you tried to reach does not exist. 

So what does it mean? That email account is deleted or what? I mean how come so quickly and can we delete our mailboxes for good?