diff --git a/target/scripts/helpers/accounts.sh b/target/scripts/helpers/accounts.sh
index 9d6c44e6..fcc6cf96 100644
--- a/target/scripts/helpers/accounts.sh
+++ b/target/scripts/helpers/accounts.sh
@@ -144,7 +144,7 @@ function _create_dovecot_alias_dummy_accounts
 
       if [[ -z ${REAL_ACC[1]} ]]
       then
-        dms_panic__misconfigured 'postfix-accounts.cf' 'alias configuration'
+        _dms_panic__misconfigured 'postfix-accounts.cf' 'alias configuration' 'immediate'
       fi
 
       # test if user has a defined quota
diff --git a/target/scripts/helpers/dns.sh b/target/scripts/helpers/dns.sh
index 1a471d16..4301fa7d 100644
--- a/target/scripts/helpers/dns.sh
+++ b/target/scripts/helpers/dns.sh
@@ -29,7 +29,7 @@ function _obtain_hostname_and_domainname
   # will result in an error that returns an empty value. This warrants a panic.
   if [[ -z ${HOSTNAME} ]]
   then
-    dms_panic__misconfigured 'obtain_hostname' '/etc/hosts'
+    _dms_panic__misconfigured 'obtain_hostname' '/etc/hosts'
   fi
 
   # If the `HOSTNAME` is more than 2 labels long (eg: mail.example.com),
diff --git a/target/scripts/helpers/error.sh b/target/scripts/helpers/error.sh
index 1dd81e55..98e75892 100644
--- a/target/scripts/helpers/error.sh
+++ b/target/scripts/helpers/error.sh
@@ -22,9 +22,10 @@ function _exit_with_error
 # PANIC_SCOPE => Optionally provide a string for debugging to better identify/locate the source of the panic.
 function dms_panic
 {
-  local PANIC_TYPE=${1}
-  local PANIC_INFO=${2}
-  local PANIC_SCOPE=${3} #optional
+  local PANIC_TYPE=${1:-}
+  local PANIC_INFO=${2:-}
+  local PANIC_SCOPE=${3-} # optional, must not be :- but just -
+  local PANIC_STRATEGY=${4:-} # optional
 
   local SHUTDOWN_MESSAGE
 
@@ -49,6 +50,10 @@ function dms_panic
       SHUTDOWN_MESSAGE="Invalid value for ${PANIC_INFO}!"
       ;;
 
+    ( 'general' )
+      SHUTDOWN_MESSAGE=${PANIC_INFO}
+      ;;
+
     ( * ) # `dms_panic` was called directly without a valid PANIC_TYPE
       SHUTDOWN_MESSAGE='Something broke :('
       ;;
@@ -56,27 +61,38 @@ function dms_panic
 
   if [[ -n ${PANIC_SCOPE:-} ]]
   then
-    _shutdown "${PANIC_SCOPE} | ${SHUTDOWN_MESSAGE}"
+    _shutdown "${PANIC_SCOPE} | ${SHUTDOWN_MESSAGE}" "${PANIC_STRATEGY}"
   else
-    _shutdown "${SHUTDOWN_MESSAGE}"
+    _shutdown "${SHUTDOWN_MESSAGE}" "${PANIC_STRATEGY}"
   fi
 }
 
 # Convenience wrappers based on type:
-function dms_panic__fail_init { dms_panic 'fail-init' "${1}" "${2}"; }
-function dms_panic__no_env { dms_panic 'no-env' "${1}" "${2}"; }
-function dms_panic__no_file { dms_panic 'no-file' "${1}" "${2}"; }
-function dms_panic__misconfigured { dms_panic 'misconfigured' "${1}" "${2}"; }
-function dms_panic__invalid_value { dms_panic 'invalid-value' "${1}" "${2}"; }
+function _dms_panic__fail_init     { dms_panic 'fail-init'     "${1:-}" "${2:-}" "${3:-}" ; }
+function _dms_panic__no_env        { dms_panic 'no-env'        "${1:-}" "${2:-}" "${3:-}" ; }
+function _dms_panic__no_file       { dms_panic 'no-file'       "${1:-}" "${2:-}" "${3:-}" ; }
+function _dms_panic__misconfigured { dms_panic 'misconfigured' "${1:-}" "${2:-}" "${3:-}" ; }
+function _dms_panic__invalid_value { dms_panic 'invalid-value' "${1:-}" "${2:-}" "${3:-}" ; }
+function _dms_panic__general       { dms_panic 'general'       "${1:-}" "${2:-}" "${3:-}" ; }
 
 # Call this method when you want to panic (i.e. emit an 'ERROR' log, and exit uncleanly).
 # `dms_panic` methods should be preferred if your failure type is supported.
 function _shutdown
 {
-  _log 'error' "${1}"
+  _log 'error' "${1:-_shutdown called without message}"
   _log 'error' 'Shutting down'
 
   sleep 1
   kill 1
-  exit 1
+
+  if [[ ${2:-wait} == 'immediate' ]]
+  then
+    # In case the user requested an immediate exit, he ensure he is not in a subshell
+    # call and exiting the whole script is safe. This way, we make the shutdown quicker.
+    exit 1
+  else
+    # We can simply wait until Supervisord has terminated all processes; this way,
+    # we do not return from a subshell call and continue as if nothing happened.
+    sleep 1000
+  fi
 }
diff --git a/target/scripts/helpers/ssl.sh b/target/scripts/helpers/ssl.sh
index 70683331..7bd7c0df 100644
--- a/target/scripts/helpers/ssl.sh
+++ b/target/scripts/helpers/ssl.sh
@@ -229,7 +229,7 @@ function _setup_ssl
 
         _log 'trace' "SSL configured with 'CA signed/custom' certificates"
       else
-        dms_panic__no_file "${TMP_KEY_WITH_FULLCHAIN}" "${SCOPE_SSL_TYPE}"
+        _dms_panic__no_file "${TMP_KEY_WITH_FULLCHAIN}" "${SCOPE_SSL_TYPE}"
       fi
       ;;
 
@@ -243,7 +243,7 @@ function _setup_ssl
       # Fail early:
       if [[ -z ${SSL_KEY_PATH} ]] && [[ -z ${SSL_CERT_PATH} ]]
       then
-        dms_panic__no_env 'SSL_KEY_PATH or SSL_CERT_PATH' "${SCOPE_SSL_TYPE}"
+        _dms_panic__no_env 'SSL_KEY_PATH or SSL_CERT_PATH' "${SCOPE_SSL_TYPE}"
       fi
 
       if [[ -n ${SSL_ALT_KEY_PATH} ]] \
@@ -251,7 +251,7 @@ function _setup_ssl
       && [[ ! -f ${SSL_ALT_KEY_PATH} ]] \
       && [[ ! -f ${SSL_ALT_CERT_PATH} ]]
       then
-        dms_panic__no_file "(ALT) ${SSL_ALT_KEY_PATH} or ${SSL_ALT_CERT_PATH}" "${SCOPE_SSL_TYPE}"
+        _dms_panic__no_file "(ALT) ${SSL_ALT_KEY_PATH} or ${SSL_ALT_CERT_PATH}" "${SCOPE_SSL_TYPE}"
       fi
 
       if [[ -f ${SSL_KEY_PATH} ]] && [[ -f ${SSL_CERT_PATH} ]]
@@ -280,7 +280,7 @@ function _setup_ssl
 
         _log 'trace' "SSL configured with 'Manual' certificates"
       else
-        dms_panic__no_file "${SSL_KEY_PATH} or ${SSL_CERT_PATH}" "${SCOPE_SSL_TYPE}"
+        _dms_panic__no_file "${SSL_KEY_PATH} or ${SSL_CERT_PATH}" "${SCOPE_SSL_TYPE}"
       fi
       ;;
 
@@ -325,7 +325,7 @@ function _setup_ssl
 
         _log 'trace' "SSL configured with 'self-signed' certificates"
       else
-        dms_panic__no_file "${SS_KEY} or ${SS_CERT}" "${SCOPE_SSL_TYPE}"
+        _dms_panic__no_file "${SS_KEY} or ${SS_CERT}" "${SCOPE_SSL_TYPE}"
       fi
       ;;
 
@@ -381,7 +381,7 @@ function _setup_ssl
       ;;
 
     ( * ) # Unknown option, panic.
-      dms_panic__invalid_value 'SSL_TYPE' "${SCOPE_TLS_LEVEL}"
+      _dms_panic__invalid_value 'SSL_TYPE' "${SCOPE_TLS_LEVEL}"
       ;;
 
   esac
@@ -404,7 +404,7 @@ function _find_letsencrypt_domain
     LETSENCRYPT_DOMAIN=${DOMAINNAME}
   else
     _log 'error' "Cannot find a valid DOMAIN for '/etc/letsencrypt/live/<DOMAIN>/', tried: '${SSL_DOMAIN}', '${HOSTNAME}', '${DOMAINNAME}'"
-    dms_panic__misconfigured 'LETSENCRYPT_DOMAIN' '_find_letsencrypt_domain'
+    _dms_panic__misconfigured 'LETSENCRYPT_DOMAIN' '_find_letsencrypt_domain'
   fi
 
   echo "${LETSENCRYPT_DOMAIN}"
@@ -418,7 +418,7 @@ function _find_letsencrypt_key
   local LETSENCRYPT_DOMAIN=${1}
   if [[ -z ${LETSENCRYPT_DOMAIN} ]]
   then
-    dms_panic__misconfigured 'LETSENCRYPT_DOMAIN' '_find_letsencrypt_key'
+    _dms_panic__misconfigured 'LETSENCRYPT_DOMAIN' '_find_letsencrypt_key'
   fi
 
   if [[ -e /etc/letsencrypt/live/${LETSENCRYPT_DOMAIN}/privkey.pem ]]
@@ -429,7 +429,7 @@ function _find_letsencrypt_key
     LETSENCRYPT_KEY='key'
   else
     _log 'error' "Cannot find key file ('privkey.pem' or 'key.pem') in '/etc/letsencrypt/live/${LETSENCRYPT_DOMAIN}/'"
-    dms_panic__misconfigured 'LETSENCRYPT_KEY' '_find_letsencrypt_key'
+    _dms_panic__misconfigured 'LETSENCRYPT_KEY' '_find_letsencrypt_key'
   fi
 
   echo "${LETSENCRYPT_KEY}"
diff --git a/target/scripts/helpers/utils.sh b/target/scripts/helpers/utils.sh
index 2ef76def..bd4d8e3c 100644
--- a/target/scripts/helpers/utils.sh
+++ b/target/scripts/helpers/utils.sh
@@ -92,13 +92,13 @@ function _replace_by_env_in_file
 {
   if [[ -z ${1+set} ]]
   then
-    dms_panic__invalid_value 'first argument unset' 'utils.sh:_replace_by_env_in_file'
+    _dms_panic__invalid_value 'first argument unset' 'utils.sh:_replace_by_env_in_file' 'immediate'
   elif [[ -z ${2+set} ]]
   then
-    dms_panic__invalid_value 'second argument unset' 'utils.sh:_replace_by_env_in_file'
+    _dms_panic__invalid_value 'second argument unset' 'utils.sh:_replace_by_env_in_file' 'immediate'
   elif [[ ! -f ${2} ]]
   then
-    dms_panic__invalid_value "file '${2}' does not exist" 'utils.sh:_replace_by_env_in_file'
+    _dms_panic__invalid_value "file '${2}' does not exist" 'utils.sh:_replace_by_env_in_file' 'immediate'
   fi
 
   local ENV_PREFIX=${1} CONFIG_FILE=${2}
diff --git a/target/scripts/start-mailserver.sh b/target/scripts/start-mailserver.sh
index 82d48013..c98639b8 100755
--- a/target/scripts/start-mailserver.sh
+++ b/target/scripts/start-mailserver.sh
@@ -60,11 +60,11 @@ function _register_functions
       ;;
 
     ( 'OIDC' )
-      _shutdown 'OIDC user account provisioning is not yet implemented'
+      _dms_panic__fail_init 'OIDC user account provisioning - it is not yet implemented' '' 'immediate'
       ;;
 
     ( * )
-      _shutdown "'${ACCOUNT_PROVISIONER}' is not a valid value for ACCOUNT_PROVISIONER"
+      _dms_panic__invalid_value "'${ACCOUNT_PROVISIONER}' is not a valid value for ACCOUNT_PROVISIONER" '' 'immediate'
       ;;
   esac
 
diff --git a/target/scripts/startup/check-stack.sh b/target/scripts/startup/check-stack.sh
index 301e1079..8fb7073f 100644
--- a/target/scripts/startup/check-stack.sh
+++ b/target/scripts/startup/check-stack.sh
@@ -38,7 +38,7 @@ function _check_hostname
   # HOSTNAME should be an FQDN (eg: hostname.domain)
   if ! grep -q -E '^(\S+[.]\S+)$' <<< "${HOSTNAME}"
   then
-    _shutdown 'Setting hostname/domainname is required'
+    _dms_panic__general 'Setting hostname/domainname is required' '' 'immediate'
   fi
 }
 
diff --git a/target/scripts/startup/daemons-stack.sh b/target/scripts/startup/daemons-stack.sh
index 99c57df6..ac2a85c2 100644
--- a/target/scripts/startup/daemons-stack.sh
+++ b/target/scripts/startup/daemons-stack.sh
@@ -29,7 +29,7 @@ function _default_start_daemon
   if [[ ${?} -ne 0 ]]
   then
     _log 'error' "${RESULT}"
-    dms_panic__fail_init "${1}"
+    _dms_panic__fail_init "${1}" '' 'immediate'
   fi
 }
 
diff --git a/target/scripts/startup/setup-stack.sh b/target/scripts/startup/setup-stack.sh
index ca2cfc12..0cd35727 100644
--- a/target/scripts/startup/setup-stack.sh
+++ b/target/scripts/startup/setup-stack.sh
@@ -87,7 +87,10 @@ function _setup_apply_fixes_after_configuration
   touch /dev/shm/supervisor.sock
 
   _log 'debug' 'Checking /var/mail permissions'
-  _chown_var_mail_if_necessary || _shutdown 'Failed to fix /var/mail permissions'
+  if ! _chown_var_mail_if_necessary
+  then
+    _dms_panic__general 'Failed to fix /var/mail permissions' '' 'immediate'
+  fi
 
   _log 'debug' 'Removing files and directories from older versions'
   rm -rf /var/mail-state/spool-postfix/{dev,etc,lib,pid,usr,private/auth}
diff --git a/target/scripts/startup/setup.d/dovecot.sh b/target/scripts/startup/setup.d/dovecot.sh
index 478610c5..cf77c979 100644
--- a/target/scripts/startup/setup.d/dovecot.sh
+++ b/target/scripts/startup/setup.d/dovecot.sh
@@ -182,7 +182,7 @@ function _setup_dovecot_local_user
       fi
     done
 
-    _shutdown 'No accounts provided - Dovecot could not be started'
+    _dms_panic__fail_init 'accounts provisioning because no accounts were provided - Dovecot could not be started' '' 'immediate'
   }
 
   __wait_until_an_account_is_added_or_shutdown
@@ -206,7 +206,7 @@ function _setup_dovecot_inet_protocols
     PROTOCOL='[::]' # IPv6 only
   else
     # Unknown value, panic.
-    dms_panic__invalid_value 'DOVECOT_INET_PROTOCOLS' "${DOVECOT_INET_PROTOCOLS}"
+    _dms_panic__invalid_value 'DOVECOT_INET_PROTOCOLS' "${DOVECOT_INET_PROTOCOLS}" 'immediate'
   fi
 
   sedfile -i "s|^#listen =.*|listen = ${PROTOCOL}|g" /etc/dovecot/dovecot.conf
diff --git a/target/scripts/startup/setup.d/networking.sh b/target/scripts/startup/setup.d/networking.sh
index febd703a..396db875 100644
--- a/target/scripts/startup/setup.d/networking.sh
+++ b/target/scripts/startup/setup.d/networking.sh
@@ -22,7 +22,7 @@ function _setup_docker_permit
   if [[ -z ${CONTAINER_IP} ]]
   then
     _log 'error' 'Detecting the container IP address failed'
-    dms_panic__misconfigured 'NETWORK_INTERFACE' 'Network Setup [docker_permit]'
+    _dms_panic__misconfigured 'NETWORK_INTERFACE' 'Network Setup [docker_permit]' 'immediate'
   fi
 
   while read -r IP