diff --git a/README.integrity-check b/README.integrity-check
new file mode 100644
index 0000000..d7d1c1c
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+++ b/README.integrity-check
@@ -0,0 +1,9 @@
+# see: 
+#  https://docs.nextcloud.com/server/31/admin_manual/issues/code_signing.html
+#  https://docs.nextcloud.com/server/31/admin_manual/issues/code_signing.html#fixing-invalid-code-integrity-messages
+#  https://docs.nextcloud.com/server/31/admin_manual/issues/code_signing.html#rescans
+
+# Error Message (/index.php/settings/admin/overview) was:
+#
+#  Some files have not passed the integrity check. List of invalid files..., 
+#  Rescan... . For more details see the documentation.