When I type a letter on keyboard it keeps repeating the letter

Sounds like the keyboard chip on the motherboard is failing. To determine this, connect a USB external keyboard up and see if you can type as fast as you normally do and it doesn't act the same as the original keyboard. If it fixes the problem, you can either have the laptop repaired by HP or just use the external keyboard. You can do the test with an external wireless keyboard too

Keyboards to wear out, but are not expensive to replace. Multiple key strikes and sticking can be caused by spilling "stuff" into the keyboard, even crumbs will do it.

replace it

If the wrong characters appear when you are typing or you are trying to use a keyboard that is different than the one that came with the computer, use the following steps to synchronize Windows to the type of keyboard you have:

1. Click Start , and type region into the Start Search field.
   
2. Select the Keyboards and Languages tab.
   
3. Click Change Keyboards .
   A Text Services and Input Languages window opens.
   Figure 3: Change Keyboard button
   
   
4. Click Add .
   Figure 4: Add button
   
   
5. Select the keyboard(s) you want to use and click OK .
   Figure 5: Add input language: US Dvorak keyboard selected.
   
   The new keyboard is added to the list of available keyboards and a keyboard icon appears on the system tray, allowing you to switch between the keyboard that you want to use with the mouse.
   Figure 6: Keyboard tray icon
   
   
6. From the Text Services and Input Languages window, select the new keyboard in the list and click Move up until it is first in the list. This makes it the default keyboard.
   Figure 7: Move up button
   
   
7. Click OK . You can now use the new keyboard. If you find that the new keyboard works well and you do not want to use the other keyboard, repeat these steps and Remove the keyboard that you do not want from the General tab of the Text Services and Input Languages window.
   

With my IBM Thinkpad, I had to hold Shift+ScrLk to turn off Number Lock.

Sounds like your Nom Lock button is on! It turns 7890 uio jkl m,. to numpad. You can just switch it off with num lock button top right on keyboard.

Best wishes,
Chillimar

Remember that if you type in the PIN "5815" (example) on the BB keyboard without holding down the ALT key you are really typing "dxwd" but you can't see it because it does not show the typed letters only the *****. Try entering the letter form of the numeric passcode. One more example. If your passcode was "1234" enter "wers".

Good luck!

sounds like one of the keys is sticking. check this out. If not uninstall driver and reinstall by plugging in again.

Caps lock is that key on the left side of your keyboard. When pressed, it makes all letters that are typed in into uppercase letters. For example; without caps lock pressed: "pressure". With caps lock pressed: "PRESSURE". If it mentions something about passwords being "case sensitive," this means that an uppercase letter A (A) is recognized differently than a lowercase letter A (a). Since you can't see your password being typed, it is important to make sure caps lock is not pressed. If this becomes too complicated, open up MS Word, notepad, or wordpad and type your password there so you can see it, then copy and paste the password into the password space on facebook. Good luck with that.

No solution here, but I'd like to second that I have a Saitek 1st gen keyboard. One day it began exhibiting the same problems that you are having. When moved to another computer it seemed to work for a month or so but then started acting up again. For my keyboard, it repeats the letters "a" "s" "m" and others. Not sure what is causing it. No spills on the keyboard and it is fairly clean.