---
title: "SL21 Firmware"
slug: "sl21-firmware"
updated: 2026-06-26T03:50:54Z
published: 2026-06-26T03:50:54Z
canonical: "knowledge.akuvox.com/sl21-firmware"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://knowledge.akuvox.com/llms.txt
> Use this file to discover all available pages before exploring further.

# SL21 Firmware

> [!NOTE]
> **NOTE:**
> 
> This lock can only be upgraded through the akubela Cloud and does not support local firmware uploads.
> 
> Refer to [the upgrade guide](/v1/docs/upgrade-akubela-smart-locks) for detailed instructions.

---

## **Release Notes**

### **Version: 21.1.10.79**

**Release Date:** June 24, 2026

#### Optimizations

1. Increased the priority of cloud-initiated reset commands to resolve an intermittent issue where property managers (PM) room reset operations in the Akuvox SmartPlus occasionally fail.

---

### **Version: 21.1.10.78**

**Release Date:** June 2, 2026

#### Fixed Bugs

1. Added support for temporary passwords synchronized from the SmartPlus cloud.
2. Added support for clearing all user profiles and credentials when resetting a room.
3. Added support for adding a lock to a new home after it has been removed from its previous home while offline.

---

### **Version: 21.1.10.75**

**Release Date:** March 21, 2026

#### Fixed Bugs

1. Fixed offline and control delay issues.
2. Fixed an issue where the lock might fail to reconnect to the network after being disconnected from Wi-Fi for over one hour.