diff --git a/nextcloud/docker-compose.smtp.yml b/nextcloud/docker-compose.smtp.yml
index b8a880f..6343eed 100644
--- a/nextcloud/docker-compose.smtp.yml
+++ b/nextcloud/docker-compose.smtp.yml
@@ -3,11 +3,11 @@ version: "3.8"
 services:
   nextcloud-fpm:
     environment:
-      SMTP_HOST: ${SMTP_HOST?err} # The hostname of the SMTP server.
+      SMTP_HOST: ${SMTP_HOST:?err} # The hostname of the SMTP server.
       SMTP_SECURE: ${SMTP_SECURE:-ssl} # Set to ssl to use SSL, or tls to use STARTTLS.
       SMTP_PORT: ${SMTP_PORT:-465}
       SMTP_AUTHTYPE: ${SMTP_AUTHTYPE:-LOGIN}
-      SMTP_NAME: ${SMTP_NAME?err}
-      SMTP_PASSWORD: ${SMTP_PASSWORD?err}
-      MAIL_FROM_ADDRESS: ${MAIL_FROM_ADDRESS}
-      MAIL_DOMAIN: ${MAIL_DOMAIN}
+      SMTP_NAME: ${SMTP_NAME:?err}
+      SMTP_PASSWORD: ${SMTP_PASSWORD:?err}
+      MAIL_FROM_ADDRESS: ${MAIL_FROM_ADDRESS:?err}
+      MAIL_DOMAIN: ${MAIL_DOMAIN:?err}