Keyboard will not type some letters

During the last few days when I type at my normal speed various letters are not printed on screen, it's the same in any program or email.
HP Pavilion zd8000 running XP with at least SP2 (Think SP3 is loaded...)Google email Google Chrome or Firefox for email. AVG 2011, Comodo, Spybot & adaware
Skype was updated in recent past.
Since oading AVG 2011 full scan takes 14 hours but that' another problem!
Any Ideas how to cure this?
Happy New Year!

Have you tried another keyboard?

Try another keyboard as suggested. If at all possible, try this keyboard on another system as well to see if the issue follows the keyboard. If it does, replace it.

I used to be a die hard AVG user but I dont like version 2011. It tends to slow a system down and the scans take forever. Ive since switched to Avast and like it a lot better.

From searching online I have found that your HP Pavilion zd8000 is a laptop. When this start happening on laptops it generally means that the keyboard is going south. What letters are not printing when you type? L? G? If that is the case you have to choices:

1. Get a usb keyboard for your laptop
2. Get a replacement keyboard.

You might want to try this....sometimes it helps:

Turn of laptop.
Unplug power cord.
Take battery off.
Press power button for about 30 seconds.
Plug power cord.
Turn on laptop to see if keys are working.
Put battery back on.

Hope that helps.

Thanks for the advice It is indeed a laptop, however I see that there are issues with Skype, if it only affects Googlemail. But it may be the keyboard.
living where I do Amazon to the rescue? However if I type slowly it works O.K. Repeated letters,I,E,R,S,D, A, L,P,N,space bar,are the usual culprits. But it came all at once rather than gradually makes me wonder before I go to replace keyboard i.e. findout first. thanks C

Depowering the computer worked! thanks for the simple fix, what have we done? all the best C

thanks to all who replied, the simple fix did not work on Monday morning so out and got a new USB keyboard. (I have a USB Mouse already) so that's it fixed for now. Looks like a new Computer will be on the shopping list for my birthday, but £4.99 is the cheap immediate cure. not the best but it work!
thanks to you all C