Users mailboxes are stored in /var/spool/mail/
The mailboxes are basically just plain text files, so they can be
manipulated with editing commands like, cp , mv etc.
Below is a basic listing of users mailboxes.
[root@server mail]# ls -la
total 3732
drwxrwxr-x 2 root mail 4096 Jan 8 13:46 .
drwxr-xr-x 18 root root 4096 Sep 7 16:04 ..
-rw-rw---- 1 accounts mail 0 Sep 7 17:02 accounts
-rw-rw---- 1 sales mail 0 Jan 8 12:07 sales
-rw-rw---- 1 jack mail 0 Oct 5 15:39 jack
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