diff --git a/client/fetch_and_update.sh b/client/fetch_and_update.sh
index ef7b7a7..0c11f92 100755
--- a/client/fetch_and_update.sh
+++ b/client/fetch_and_update.sh
@@ -10,7 +10,7 @@ mkdir -p "${IMAGES}"
 BOOT="/isodevice"
 
 FETCHER_FLAGS="$(cat /icon/config/fetcher.flags)"
-if -f /icon/config/update_grub.flags; then
+if test -f /icon/config/update_grub.flags; then
   UPDATE_GRUB_FLAGS="$(cat /icon/config/update_grub.flags)"
 fi
 CA_CERT="/icon/config/ca.image.cert.pem"