Like all processes,
the DansGuardian server/daemon process
has a
user and
group.
The user/group of each process
controls how the operating system grants permissions to it,
particularly access to various files and directories.
Typically operation is simplest
if DansGuardian, its local proxy backend (for example Squid),
and any anti-virus daemon
all run as the same user/group
If not specified, DansGuardian will default
to running as whatever user and group
were built in
(typically either nobody/nobody or nouser/nogroup).
It's probably better to explititly specify
some user userid/groupid
than to chance file permissions as necessary
to make the built in settings work.