diff --git a/services/notes.js b/services/notes.js
index a568f06b5..7cbf41d8b 100644
--- a/services/notes.js
+++ b/services/notes.js
@@ -81,6 +81,12 @@ async function protectNoteRecursively(noteId, dataKey, protect) {
     }
 }
 
+function decryptNote(note, dataKey) {
+    note.note_title = data_encryption.decryptString(dataKey, data_encryption.noteTitleIv(note.note_id), note.note_title);
+    note.note_text = data_encryption.decryptString(dataKey, data_encryption.noteTextIv(note.note_id), note.note_text);
+    note.is_protected = false;
+}
+
 async function protectNote(note, dataKey, protect) {
     let changed = false;
 
@@ -92,9 +98,7 @@ async function protectNote(note, dataKey, protect) {
         changed = true;
     }
     else if (!protect && note.is_protected) {
-        note.note_title = data_encryption.decryptString(dataKey, data_encryption.noteTitleIv(note.note_id), note.note_title);
-        note.note_text = data_encryption.decryptString(dataKey, data_encryption.noteTextIv(note.note_id), note.note_text);
-        note.is_protected = false;
+        decryptNote(note, dataKey);
 
         changed = true;
     }
@@ -150,14 +154,19 @@ async function updateNote(noteId, newNote, ctx) {
         if (!existingNoteHistoryId && (now - newNote.detail.date_created) >= historySnapshotTimeInterval) {
             const oldNote = await sql.getSingleResult("SELECT * FROM notes WHERE note_id = ?", [noteId]);
 
+            if (oldNote.is_protected) {
+                decryptNote(oldNote, ctx.getDataKey());
+            }
+
             const newNoteHistoryId = utils.newNoteHistoryId();
 
             await sql.insert('notes_history', {
                 note_history_id: newNoteHistoryId,
                 note_id: noteId,
+                // title and text should be decrypted now
                 note_title: oldNote.note_title,
                 note_text: oldNote.note_text,
-                is_protected: oldNote.is_protected,
+                is_protected: 0, // will be fixed in the protectNoteHistory() call
                 date_modified_from: oldNote.date_modified,
                 date_modified_to: now
             });