• Low battery charge
• Moving the USB receiver from one USB port to another
• Moving the USB receiver to another computer
• Plugging the USB receiver into a USB hub, KVM switch or other unsupported device (NOTE: Your USB receiver must be plugged directly into your computer.)
• Using your wireless keyboard on metal surfaces

• Radio frequency (RF) interference from other sources, such as:

  • Wireless speakers
  • Computer power supplies
  • Monitors
  • Cell phones
  • Garage door openers

Before reconnecting your K800

1. Make sure the batteries in your K800 are fully charged.
2. Make sure your keyboard is turned on. For instructions on how to turn your keyboard on and off, see answer null.
3. Make sure the USB receiver is securely plugged directly into a working USB port on your computer.
4. Turn your computer on.

Reconnecting your K800

1. Download and install the correct version of the Logitech SetPoint mouse and keyboard software from the K800 Downloads page.
2. Launch the Logitech Unifying Software (which was included in SetPoint) from Start > Programs > Logitech > Unifying > Logitech Unifying Software.
3. When the Logitech Unifying Software Welcome screen shown below displays, click Next to continue.

   

4. Follow the on-screen instructions to turn your K800 off and then back on.

   

   When your K800 is detected, you'll see this confirmation message:

   

5. Type a test message in the text field to verify the keyboard is working.
6. Once you've confirmed the keyboard is working, choose "Yes" and then click Next to continue.
7. Click Finish to exit the Logitech Unifying Software. Your K800 should now be connected.