Logitech K750 Troubleshooting Manual page 14

Having to turn the K750 on/off for the keyboard to work again
The K750 Wireless Solar Keyboard is powered by the ambient light in the room. If something is
consistently draining the power, the keyboard will time-out after awhile.
For example, A few keys are continually being pressed because the corner of a book is resting on
top of them.
In order for the keyboard to start working again, it has to be turned off and then back on.
K750 keyboard battery level shows as low in a well-lit room
If your battery level shows as low even in a well-lit room, try the following:

Check the current battery status in the Solar App
NOTE: If you don't already have the Solar App installed, see answer
and usage instructions.

Press the Check-Light button above the number pad and verify that the light intensity
level in the room is strong enough

Place the keyboard in a well-lit room or in direct sunlight for a couple of hours and then
check the battery status
My Unifying mouse or keyboard wakes the computer even when it is set not to
Symptom
After disabling the ability to wake-up the system in Windows Device Manager, the Unifying
mouse or keyboard still brings the system out of sleep mode.
Solution
Even if you bought a mouse-only or keyboard-only product, the Unifying receiver that came
with it still enumerates for both the mouse and keyboard interfaces.
Example
If you have two mice attached, then you would need to uncheck the "Allow this device to wake
the computer" option for both mice plus a keyboard in the Windows Device Manager.
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