Logitech FAQ Resource Central

Ok, this is one of the most popular issues that can happen to an owner of Logitech cordless desktop sets. For example, you bought a Logitech Cordless Desktop EX110, EX90, MX3200, etc.. Everything was working perfectly fine during the past 3 months and all of a sudden after a battery change, keyboard will not work! The funny thing is that the mouse is still functional!

What could go wrong for a desktop set imbued with Logitech's SecureConnect Technology? Logitech claims that you will never need to do manual connection again after the first connection. Normally if you are experiencing this issue, even by doing manual connection will not get the keyboard to connect. What can cause the keyboard to have lost sync with the receiver? Let's explore some of the possible causes and some simple steps to rectify the problem.

Corrupted encryption data in keyboard
A battery change could have corrupted the encryption data stored in the keyboard. No matter how you try to reconnect your devices, due to the corrupted data; the receiver cannot recognize the data from the keyboard.

Corrupted encryption data in receiver
Plugging and unplugging the receiver may have a slight chance of corrupting the encryption data stored in the receiver. Pretty much like unplugging an active thumb drive from the USB port.

Clash of the same RFID
Chances are very slim but if there are other people within the same frequency range using the same keyboard with the exact same RFID. I doubt this will happen but who knows.

Encryption data not matching
Your keyboard is securely encrypted. However, the receiver is lost or damaged to a point that you have obtained another similar receiver for who knows how you did it. Due to the encryption not matching the previous one stored in the keyboard, the receiver will not connect to the keyboard.

There are definitely more possibilities but let's just look at what we can do to fix the problem. Since both the devices are encrypted, let's decrypt them. When you decrypt the devices, it simply means that enhanced security features will temporarily be disabled. This will allow both the devices to reconnect. Perform these steps in exact order for decryption:

1. If you have Logitech software installed. e.g. SetPoint. Exit it via the system tray by right-clicking and selecting "Exit". If you do not know how to do so, just remove all Logitech software from your computer.

2. Make sure your keyboard has fresh alkaline batteries installed and the polarities are correct.

3. Press Left Alt + Left Ctrl + F12 together on your keyboard and release. Note the bold lefts.

4. Press connect button on the receiver and release.

5. Press connect button underneath the keyboard and release.

6. Press ESC key on your keyboard.

If you have done the steps correctly, your keyboard should now be connected. If not, perform the decryption steps a couple more times will help. Sometimes changing the receiver to a different USB port after the steps will help too.

Once you got your keyboard to work, it's a good idea to re-encrypt the signals. Just install or launch SetPoint and perform step number 3 from above will allow you follow the on-screen instructions to encrypt your signals.