This is most likely to happen on a normal GUI system like Ubuntu or Linux Mint. If you or the user is meant to have sudo / root privileges it is as simple as editing the following files:
Now assume your username is "iamtheuser"
Find the above lines and add a comma and "ia........
This is an important feature a failed read can genuinely occur if a temporary file has been removed or if you try backing up a sysetm file in /proc /sys (which you shouldn't really anyway).
The way to fix this is the following switch:
sudo tar --ignore-failed-read -czvf mycomputer-backup.tar.gz --exclude=/home/otheruser/* --exclude=/proc/* --e........
*remember to apply changes you need to run "newaliases" after editing /etc/aliases
one thing I don't get is that it doesn't allow you to specify the whole e-mail address on the left-hand side
postalias: warning: /etc/aliases, line 109: name must be local (if you try the above)
It works more like this: