diff --git a/target/scripts/startup/setup.d/oauth2.sh b/target/scripts/startup/setup.d/oauth2.sh
index bec4e809..20e9ffd1 100644
--- a/target/scripts/startup/setup.d/oauth2.sh
+++ b/target/scripts/startup/setup.d/oauth2.sh
@@ -4,7 +4,7 @@ function _setup_oauth2() {
   _log 'debug' 'Setting up OAUTH2'
 
   # Enable OAuth2 PassDB (Authentication):
-  sed -i -e '/\!include auth-oauth2\.conf\.ext/s/^#//' /etc/dovecot/conf.d/10-auth.conf
+  sedfile -i -e '/\!include auth-oauth2\.conf\.ext/s/^#//' /etc/dovecot/conf.d/10-auth.conf
   _replace_by_env_in_file 'OAUTH2_' '/etc/dovecot/dovecot-oauth2.conf.ext'
 
   return 0