The cursor moves but the clicking doesn't work

It's bad and needs to be changed, ie if you must keep enjoying the old functions.

sounds like your synaptic touch pad settings have been tampered with. make sure driver is installed the go into control panel and click on the synaptic touch pad and check the settings

This typically happens when the typist's palms touch the touchpad, which the pad treats as a mouse click. See if the cursor is jumping to where the pointer is.
Most touchpads have a control panel (usually part of the MOUSE Control Panel) where you can reduce the sensitivity (or disable) the left click function from tapping the touchpad.

and old CQ56, super old that.
no oS stated, XP the virus magnet?

who asks for ps bios password or windows login screen.?
did you remove all other usb devices, fur SURE MICE?

id say virus infected.
then bad pad driver,
in device manager, see that pad there, click update
do so , online.
C56 tells me nothing the model has numbers at the end
if still running HP windows,(not hacked with MS disks)
the drivers for HP pad are at HP
but i can look for you lacking that a full model number.
here ill guess to teach you how HP works

CQ56-100us (us means us keyboard there)

ill pretend you said XP 32bit
and land here
then got the driver for XP here called.
Synaptics TouchPad Driver for Microsoft Windows XP
15.0.18.0 Rev. A (get it load and and use only that if i guessed right.

https://support.hp.com/us-en/drivers/selfservice/compaq-presario-cq56-100-notebook-pc-series/4247498

Try the mouse settings in the control panel, also try uninstall any touchpad software and remove any touchpad software from running when the pc boots.
To do this either type msconfig into the run/search box or a program like cc cleaner under tools/startup

Hi,
You have perhaps a CD for your presario Compaq computer. Try to insert that in your CD rom and look for the touch pad to enable. Or just look for the touch pad in your device manager and enable it. To open the device manager, right click computer and go to properties and click hardware then click device manager. If touch pad is in the list enable it.

Thanks...

Try goign into the touch pad settings and tunring the sensitivity way up. either by its software or goto the control panel and mouse settings. hope this helps in some way.

Dear Sir,

Generally for compaq there is lock for touch pad you can see a moving lock below or above the touch pad. If locked the tochpad button,touch pad not sensitive.So open the lock and now you can move pointer using touch pad. see this pic
http://icerazerstudios.com/wp-content/gallery/random%20images/touchpad.jpg

there is black color button lock appear at the upper border of touchpad.

Do you mean when you just tap the pad w/ ur finger? if so this is a setting that can be turned on and off. Have you or anyone been pilfering through the settings?
  `Nbryson

In windows xp go into start menu, then into control panel then click on appearance and themes, then move your mouse over to mouse pointers click on it , uncheck "enhance pointer precision, and click apply, that will stop the mouse from acting crazy, this will work with dell mouse pointers and most.