diff --git a/system_setup/install.sh b/system_setup/install.sh
index c25ac49..25ce3b6 100755
--- a/system_setup/install.sh
+++ b/system_setup/install.sh
@@ -408,7 +408,7 @@ if [[ -n "$EXISTING_OEMDRV_DEV" ]]; then
                 || die "git fetch failed."
             git -C "$MOUNT_POINT" checkout -B "$REPO_BRANCH" FETCH_HEAD \
                 || die "git checkout failed."
-            source "$MOUNT_POINT/system_setup/setup_system.inc.sh"
+            source "$MOUNT_POINT/system_setup/setup_system.inc.sh" --missingconfok
             finish_install "$EXISTING_OEMDRV_DEV"
             exit 0
         fi