Hi Henk,
Were there any changes (hardware or software) made to the computer prior to the issue?
I understand the frustration when things don’t work as expected.
There are a few different kinds of keyboards. The most common is a physical, external keyboard that you plug into your PC. A PC with a touchscreen also has a touch keyboard. When you’re using a Windows PC with a touchscreen, tap in a text field or other area where you can type and the touch keyboard appears.
Windows also has On-Screen Keyboard (OSK), an Ease of Access tool. You can use OSK instead of relying on the physical keyboard to move around your PC and enter text. You don’t need a touchscreen to use On-Screen Keyboard. OSK displays a visual keyboard with all the standard keys. You can select keys using the mouse or another pointing device, or you can use a physical single key or group of keys to cycle through the keys on the screen.
Check if the issue occurs while using the On-screen keyboard.
**http://windows.microsoft.com/en-us/windows-8/type-with-the-on-screen-keyboard**
If you need any further assistance with Windows Operating System, please post your query on Microsoft Community Forums and we’ll be glad to assist you with it.