diff --git a/scripts/install b/scripts/install
index 884eee5..f51ed69 100644
--- a/scripts/install
+++ b/scripts/install
@@ -82,7 +82,7 @@ sandboxdomain=sandbox-$domain
 # We don't test that in CI
 if ! [ ${PACKAGE_CHECK_EXEC:-0} -eq 1 ]; then
 	yunohost domain add $sandboxdomain
-	yunohost domain config set $sandboxdomain -a mail_in=0&mail_out=0
+	yunohost domain config set $sandboxdomain -a "mail_in=0&mail_out=0"
 fi
 
 #=================================================