Hi I am attempting to configure squirrelmail. I have followed these steps:
1) downloaded tar
2) extracted tar; cd to extracted tar's director; made attachments dir; and attempt to reassign ownership using chown.
tar xzvf squirrelmail-1.4.3.a.tar.gz
chown -R www-data data attachments
[I] Error is thrown:
chown: 'www-data' : invalid user
When I looked in chown --help this appears to be formated ok. One thing that I am not sure of is wether or not www-data has to be an existing linux user. If so I am not sure how to determine whether it is or is not?
I have performed many chown commands in the last day or so and all with success so I can't understand why this is failing?
Your help in determining why this might be failing is greatly appreciated.