diff --git a/imageroot/bin/wait-startup b/imageroot/bin/wait-startup
index d9bcef2..d4e8f86 100755
--- a/imageroot/bin/wait-startup
+++ b/imageroot/bin/wait-startup
@@ -6,7 +6,6 @@
 #
 
 import sys
-import json
 import time
 import subprocess
 
@@ -16,16 +15,23 @@ def occ(args):
     return (p.returncode, p.stdout)
 
 # wait after nextcloud-app is ready
+exit_code_messages = {1: "maintenance mode enabled", 2: "needs DB upgrade"}
 max_tries = 60
 i = 0
+last_ret = None
 while i < max_tries:
     i = i+1
     try:
-        ret, out = occ(["status", "--output", "json"])
-        status = json.loads(out)
-        if status["installed"]:
+        ret, out = occ(["status", "-e"])
+        last_ret = ret
+        if ret == 0:
             break
-        print(f"wait-startup: waiting for nextcloud-app ({i})", file=sys.stderr)
-        time.sleep(1)
+        status_msg = exit_code_messages.get(ret, "not ready")
+        print(f"wait-startup: waiting for nextcloud-app ({i}): occ status exit code={ret} ({status_msg})", file=sys.stderr)
     except Exception as e:
-        continue
+        print(f"wait-startup: exception ({i}): {e}", file=sys.stderr)
+    time.sleep(1)
+else:
+    status_msg = exit_code_messages.get(last_ret, "not ready")
+    print(f"wait-startup: Nextcloud did not become ready in time (last status: {status_msg})", file=sys.stderr)
+    sys.exit(1)