I recently upgraded my CCU2 to a CCU3, but I encountered some challenges with the firmware and recovery mode. After some troubleshooting, I thought I’d share my experience and what I’ve learned along the way. Hopefully, this can help others facing similar issues.Earlier this year, I decided to switch from my trusty CCU2 to a CCU3 for better functionality and connectivity. However, the transition wasn’t as smooth as I hoped. The first CCU3 I received had some connectivity issues, particularly with certain devices, which was frustrating given how seamless everything was with the CCU2. To resolve this, I opted for a CCU3 with an external antenna, which solved the connectivity problems immediately.I initially flashed the CCU3 with the original firmware (ccu3-3.53.34.tgz) and later switched to RaspberryMatic (RaspberryMatic-3.53.34.20201121-ccu3.tgz) for added functionality. Now that I’ve got the replacement CCU3 with the external antenna up and running perfectly, I wanted to return the first CCU3. To do this, I needed to restore it to its original firmware or at least get it working again so I could sell it.Here’s where things got tricky. I tried flashing the original firmware back onto the first CCU3, but the update process took an unusually long time—significantly longer than any previous updates. After a day of waiting, I had to give up and restart the device. Unfortunately, this left me stuck in the Recovery Menu, unable to perform any further actions. Even attempting to factory reset or flash a new firmware resulted in the browser disconnecting after a few seconds.I’ve tried reaching out for help, but the solutions suggested so far haven’t worked. I’m now wondering if there’s a way to access the CCU3 via telnet or SSH without enabling these services through the web interface. If anyone has experience with similar issues or knows of a workaround, I’d greatly appreciate the advice.This experience has taught me the importance of documenting every step when dealing with firmware changes and backups. It’s also highlighted how crucial it is to have a reliable backup plan, especially when dealing with devices that are critical to a smart home setup.If anyone has encountered similar issues or has tips on how to resolve them, I’d love to hear your insights. Let’s keep the conversation going and help each other navigate these sometimes tricky technical challenges!