Arduino Micro, driver problem

I will usa a Arduino Micro as a keyboard emulator to my CNC system (Mach 3).
Using xp and when I manualy try to install the driver the Xp can't find the driver.
I's a complete new machine.
I have tryed to install it on another PC xp, all works.
Same when I install on a Win 7 machine, all ok
I need to get my CNC machine running.
If I remove the bootstrap do I then need a driver?
Please help!

Check out "System Properties" and "Hardware" click and verify you are not blocked. Make sure you are logged in as Administrator.

Can't really help with the driver issue but are you trying to do something special that requires an Arduino? There are a few button modules that will emulate a keyboard or you can use a xbox 360 controller with mach3. That gives you several buttons and you can use the joystick to move the cutting head

I have Checked the system properties, i's ok same on all computer that I have tested.
Also installed a XBOX360 controller for test, fantasic!
If I installed the Arduino Micro direct in the USB port it works, via hub it will not work. Askk for driver and it will not acept the driver.
Tryed to burn the software via Atmel studio 6, but I am not shure to remove the Arduino bootloader, can anybody help me?

If you burn any hex file to the microcontroller, the bootloader will be over-written and you will have to burn the bootloader back on to enable sketch uploading capability.

If the the bootloader is over-written, why does the pc ask for driver?

The Micro like the Leonardo has a USB function as part of its core software. That's probably what you are seeing.

Automatic (Software) Reset and Bootloader Initiation
Rather than requiring a physical press of the reset button before an upload, the Micro is designed in a way that allows it to be reset by software running on a connected computer. The reset is triggered when the Micro's virtual (CDC) serial / COM port is opened at 1200 baud and then closed. When this happens, the processor will reset, breaking the USB connection to the computer (meaning that the virtual serial / COM port will disappear). After the processor resets, the bootloader starts, remaining active for about 8 seconds. The bootloader can also be initiated by pressing the reset button on the Micro. Note that when the board first powers up, it will jump straight to the user sketch, if present, rather than initiating the bootloader.
Because of the way the Micro handles reset it's best to let the Arduino software try to initiate the reset before uploading, especially if you are in the habit of pressing the reset button before uploading on other boards. If the software can't reset the board you can always start the bootloader by pressing the reset button on the board.