libraries

2 weeks now I have been trying to use libraries with sketchs, first lcd, now I really need to get the ps2keyboard to work.
I have a sketch that runs a 48 position turntable using a stepper motor that I am currently controlling with the serial monitor. I need to get it to run with just a keyboard attatched to the Arduino. I have done everything I can think of but keep coming up with an error on keyboard.begin(DataPin, IRQpin); I am just trying to run the simple test at this point.
(no matching function for call to ps2keyboard). I'm sure its something stupid I am overlooking, but cant figure it out. I thought it was the AVR/io.h or something i don't know?! help if you can, or just send me a sianide pill

post your sketch so far.
post your schematics.

I have done everything I can think of

What have you tried for variations?
What did you expect?
what was the outcome?

The more you describe your problem and project in detail the better answers you can expect.

OK I got it working but on a different pc. I reloded on the original computer a couple times, tried everything, no go. Found an old laptop and loaded arduino on it and the library in question and it compiled straight away so I have it working but still must have some silly issue with the original computer I was trying to use. I wrote a few sketches with it and they all worked fine, but with any library I had to download off the internet , such as the I2c and ps2keyboard!?
Thanks for the response.