Confirmation email not being sent

Summary

After registering a new user no confirmation mail is received. Requesting new confirmation also doesn't work. I configured everything relevant to smtp with my gmail account as described in the documentation: https://docs.gitlab.com/omnibus/settings/smtp.html

and also successfully sent an email via Notify.test_email('destination_email@address.com', 'Message Subject', 'Message Body').deliver_now to one of my user accounts.

Relevant logs and/or screenshots

# From /var/log/gitlab/nginx/gitlab_access.log
194.114.104.125 - - [02/Aug/2018:13:42:12 +0000] "GET /users/confirmation/new HTTP/1.1" 200 3303 "http://46.16.74.149:1235/users/almost_there" "Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Firefox/52.0"
194.114.104.125 - - [02/Aug/2018:13:42:16 +0000] "POST /users/confirmation HTTP/1.1" 302 109 "http://46.16.74.149:1235/users/confirmation/new" "Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Firefox/52.0"
194.114.104.125 - - [02/Aug/2018:13:42:17 +0000] "GET /users/almost_there HTTP/1.1" 200 2654 "http://46.16.74.149:1235/users/confirmation/new" "Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Firefox/52.0"

Results of GitLab environment info

Expand for output related to GitLab environment info 
System information
System:		Ubuntu 18.04
Proxy:		no
Current User:	git
Using RVM:	no
Ruby Version:	2.4.4p296
Gem Version:	2.7.6
Bundler Version:1.16.2
Rake Version:	12.3.1
Redis Version:	3.2.11
Git Version:	2.17.1
Sidekiq Version:5.1.3
Go Version:	unknown


GitLab information
Version:	11.1.4-ee
Revision:	d17962f9345
Directory:	/opt/gitlab/embedded/service/gitlab-rails
DB Adapter:	postgresql
DB Version:	9.6.8
URL:		http://XX.XX.XX.XXX:1235
HTTP Clone URL:	http://XX.XX.XX.XXX:1235/some-group/some-project.git
SSH Clone URL:	git@XX.XX.XX.XXX:some-group/some-project.git
Elasticsearch:	no
Geo:		no
Using LDAP:	no
Using Omniauth:	no


GitLab Shell
Version:	7.1.4
Repository storage paths:
  • default: /var/opt/gitlab/git-data/repositories Hooks: /opt/gitlab/embedded/service/gitlab-shell/hooks Git: /opt/gitlab/embedded/bin/git

Results of GitLab application Check

Expand for output related to the GitLab application check 
Checking GitLab Shell ...


GitLab Shell version >= 7.1.4 ? ... OK (7.1.4)
Repo base directory exists?
default... yes
Repo storage directories are symlinks?
default... no
Repo paths owned by git:root, or git:git?
default... yes
Repo paths access is drwxrws---?
default... yes
hooks directories in repos are links: ...
3/1 ... ok
Running /opt/gitlab/embedded/service/gitlab-shell/bin/check
Check GitLab API access: OK
Redis available via internal API: OK


Access to /var/opt/gitlab/.ssh/authorized_keys: OK
gitlab-shell self-check successful


Checking GitLab Shell ... Finished


Checking Sidekiq ...


Running? ... yes
Number of Sidekiq processes ... 1


Checking Sidekiq ... Finished


Reply by email is disabled in config/gitlab.yml
Checking LDAP ...


LDAP is disabled in config/gitlab.yml


Checking LDAP ... Finished


Checking GitLab ...


Git configured correctly? ... yes
Database config exists? ... yes
All migrations up? ... yes
Database contains orphaned GroupMembers? ... no
GitLab config exists? ... yes
GitLab config up to date? ... yes
Log directory writable? ... yes
Tmp directory writable? ... yes
Uploads directory exists? ... yes
Uploads directory has correct permissions? ... yes
Uploads directory tmp has correct permissions? ... yes
Init script exists? ... skipped (omnibus-gitlab has no init script)
Init script up-to-date? ... skipped (omnibus-gitlab has no init script)
Projects have namespace: ...
3/1 ... yes
Redis version >= 2.8.0? ... yes
Ruby version >= 2.3.5 ? ... yes (2.4.4)
Git version >= 2.9.5 ? ... yes (2.17.1)
Git user has default SSH configuration? ... yes
Active users: ... 3
Elasticsearch version 5.1 - 5.5? ... skipped (elasticsearch is disabled)


Checking GitLab ... Finished
Edited by Rich Stone