There are a number of potential causes for an unresponsive keyboard, but most often the problem lies within either the hardware or software of the computer itself.
Hardware
One of the most common causes of an unresponsive keyboard is a physical issue with the keyboard. This could be due to damage, dirt or dust build-up, or even a lack of power.
Damage: Damage can occur when something presses down on the keys too hard for a long time, or when a drink is spilled on the keyboard. These types of situations can cause the keys to stick, or for them to stop functioning altogether.
Dirt/Dust Build-up: When dirt and dust build up in the gaps between the keys, it can prevent them from accurately registering when you press them. A good cleaning with a compressed air can may be able to help eliminate this problem.
Lack of Power: If the keyboard isn’t receiving power, it will not be able to function correctly. This could be caused by a problem with the power cable or the USB port that it’s plugged into.
Software
The issue could also be a result of a software issue, such as incorrect settings or outdated drivers.
Incorrect Settings: Check to make sure that the keyboard is properly configured in the operating system. In Windows, go to the Control Panel and check the Keyboard settings.
Outdated Drivers: Outdated drivers can cause an array of problems, including an unresponsive keyboard. Make sure that you have the most up-to-date drivers installed on your system.
Other Potential Causes
In some cases, the issue could be due to a problem outside of the computer.
External Devices: Make sure that any external devices (such as gaming pads or external mice) are disconnected before troubleshooting the keyboard. Such devices can interfere with the keyboard’s functioning.
Viruses/Malware: Viruses and malware can sometimes interfere with the functioning of the keyboard. If you suspect that this might be the case, make sure to run a full system scan with up-to-date antivirus software.
If none of these solutions solve the issue, it may be necessary to try a different keyboard or to have a qualified technician investigate the problem further.