Hi all,
I have replaced my old keyboard with the same model new. It is an advent model. The new appears to have the same problem which makes me think it is a PC fault.
Whenever I press the Ditto ( " ) key I get the at ( @ ) on the screen and visa versa. Any ideas as to why this is happening?
Thanks
Richard.

You are probably in "Num Lk" mode. Look at the keyboard towards the top and see if you see the NumLk key set. Take it off NumLk. Sometimes the keys next to it are used a lot and you inadvertently might hit the NumLk key.

Check to see what your locale is. In other words, are you using the US Keyboard or some other language. Check your Regional and Language options under Control Panel