Bug#1099474: colord: On update dpkg colord exits with fatal: The user `colord' already exists, but is not a system user. Exiting.

[Petter Reinholdtsen]

[Sebastian Bremicker]
> on updating colord I encounter

I ran into this too.  I got around it by removing the user before doing the upgrade.

# getent passwd colord
colord:x:105:112:colord colour management daemon,,,:/var/lib/colord:/bin/false
# deluser colord
# apt dist-upgrade
[...]
# getent passwd colord
colord:x:105:112:colord colour management daemon,,,:/var/lib/colord:/usr/sbin/nologin
#

-- 
Happy hacking
Petter Reinholdtsen