diff --git a/.mergify.yml b/.mergify.yml
deleted file mode 100644
index 927bfc3e..00000000
--- a/.mergify.yml
+++ /dev/null
@@ -1,23 +0,0 @@
-pull_request_rules:
-  - name: Successful travis and 2 approved reviews
-    conditions:
-      - status-success=continuous-integration/travis-ci/pr
-      - label!=["status"/wip","status/blocked"]
-      - "#approved-reviews-by>=2"
-    actions:
-      merge:
-        method: merge
-      dismiss_reviews:
-        approved: true
-
-  - name: Trusted author, successful travis and 1 approved review
-    conditions:
-      - author~=(kaiyou|muhlemmer|mildred|HorayNarea|adi90x|hoellen|ofthesun9)
-      - status-success=continuous-integration/travis-ci/pr
-      - label!=["status"/wip","status/blocked","review/need2"]
-      - "#approved-reviews-by>=1"
-    actions:
-      merge:
-        method: merge
-      dismiss_reviews:
-        approved: true
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 07b5b164..2b068547 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -116,6 +116,7 @@ v1.6.0 - unreleased
 - Bug: Don't recursivly chown on mailboxes ([#776](https://github.com/Mailu/Mailu/issues/776))
 - Bug: Fix forced password input for user edit ([#745](https://github.com/Mailu/Mailu/issues/745))
 - Bug: Fetched accounts: Password field is of type "text" ([#789](https://github.com/Mailu/Mailu/issues/789))
+- Bug: DOMAIN_REGISTRATION=False in .env was not treated correctly ([#830](https://github.com/Mailu/Mailu/issues/830))
 
 v1.5.1 - 2017-11-21
 -------------------
diff --git a/core/admin/mailu/configuration.py b/core/admin/mailu/configuration.py
index 95004017..a8cd3e25 100644
--- a/core/admin/mailu/configuration.py
+++ b/core/admin/mailu/configuration.py
@@ -30,11 +30,11 @@ DEFAULT_CONFIG = {
     'POSTMASTER': 'postmaster',
     'TLS_FLAVOR': 'cert',
     'AUTH_RATELIMIT': '10/minute;1000/hour',
-    'DISABLE_STATISTICS': 'False',
+    'DISABLE_STATISTICS': False,
     # Mail settings
     'DMARC_RUA': None,
     'DMARC_RUF': None,
-    'WELCOME': 'False',
+    'WELCOME': False,
     'WELCOME_SUBJECT': 'Dummy welcome topic',
     'WELCOME_BODY': 'Dummy welcome body',
     'DKIM_SELECTOR': 'dkim',
@@ -74,13 +74,21 @@ class ConfigManager(dict):
     def __init__(self):
         self.config = dict()
 
+    def __coerce_value(self, value):
+        if isinstance(value, str) and value.lower() in ('true','yes'):
+            return True
+        elif isinstance(value, str) and value.lower() in ('false', 'no'):
+            return False
+        return value
+
     def init_app(self, app):
         self.config.update(app.config)
         # get environment variables
         self.config.update({
-            key: os.environ.get(key, value)
+            key: self.__coerce_value(os.environ.get(key, value))
             for key, value in DEFAULT_CONFIG.items()
         })
+
         # automatically set the sqlalchemy string
         if self.config['DB_FLAVOR']:
             template = self.DB_TEMPLATES[self.config['DB_FLAVOR']]
diff --git a/core/admin/mailu/manage.py b/core/admin/mailu/manage.py
index 4846c2d6..e11644e7 100644
--- a/core/admin/mailu/manage.py
+++ b/core/admin/mailu/manage.py
@@ -31,7 +31,7 @@ def advertise():
         instance_id = str(uuid.uuid4())
         with open(app.config["INSTANCE_ID_PATH"], "w") as handle:
             handle.write(instance_id)
-    if app.config["DISABLE_STATISTICS"].lower() != "true":
+    if not app.config["DISABLE_STATISTICS"]:
         try:
             socket.gethostbyname(app.config["STATS_ENDPOINT"].format(instance_id))
         except:
diff --git a/core/admin/mailu/models.py b/core/admin/mailu/models.py
index 4168b606..27165e8e 100644
--- a/core/admin/mailu/models.py
+++ b/core/admin/mailu/models.py
@@ -410,7 +410,7 @@ class User(Base, Email):
         return emails
 
     def send_welcome(self):
-        if app.config["WELCOME"].lower() == "true":
+        if app.config["WELCOME"]:
             self.sendmail(app.config["WELCOME_SUBJECT"],
                 app.config["WELCOME_BODY"])
 
diff --git a/docs/compose/setup.rst b/docs/compose/setup.rst
index 942a368e..3ff1f678 100644
--- a/docs/compose/setup.rst
+++ b/docs/compose/setup.rst
@@ -154,3 +154,5 @@ Finally, you must create the initial admin user account:
   docker-compose exec admin flask mailu admin me example.net password
 
 This will create a user named ``me@example.net`` with password ``password`` and administration privileges. Connect to the Web admin interface and change the password to a strong one.
+
+  .. note:: It is vitally important that either a user with the same email as ``POSTMASTER`` in your ``.env`` exists, or you remember to create an alias with this name after you log in. All kinds of strange errors will occur as a result of not doing so!