Keypad problem

[fine]

I am a new member just found the site.
I have a Chinese mid tablet and bought an add on keypad from Maplin.

,The Keypad works fine tablet but when the usb is removed from the tablet ,the tablet freezes and has to have a reset.

Any help please

 

[probbiethe1]

is there something in the notification bar that lets you safely remove the usb?

 

[fine]

There is nothing on screen at all that shows the keypad is connected.