I just got a used laptop, and the left button on the touchpad keeps triggering when I’m not touching it. I got a USB mouse hoping that would override the touchpad, but it doesn’t. When I go into the Control Panel it will let me disable the external mouse but not the touchpad. Is there another way to shut it off?
On some laptops you can disable the touchpad in the BIOS.
I’m using a Toshiba laptop at the moment. The key combination FN-F9 disables or enables the touchpad.
I have an HP notebook and just disabled the touch pad with a button at the top middle of the pad. A blue light shows that the touch pad is enabled, amber indicates it is disabled.
Thanks for the question.
I have an Acer Aspire, and the combo for me is Fn-F7.
S^G
Have you tried Googling for a manual for that paritcular model? As we’ve seen up-thread, there is no pattern to which Fn-whatever keys do what, but there probably is a key combo which does what you need.
What make and model is it?
Check your keyboard. Some buttons should have blue markings on them. Look for a blue picture of a finger poking a square. Hold down the Fn button and press the finger poking button.
That should turn off the touchpad.
That said for laptops in my experience once you get used to the touchpad it’s better then the mouse by far because you can lay down and use it with the laptop on your chest.
I have a little icon on the taskbar thingie over by the clock that says Dell Touchpad. Clicking on that opens a screen where I can disable the touchpad. Maybe yours has something similar?
It’s not the touchpad per se I’m having trouble with. It’s the constant accidental mouse clicks while I’m typing. I’ve found if I don’t rest my forearms on the laptop, and I type like I just painted my fingernails I don’t have the problem. Not a great solution for a variety of reasons 
Thanks for the suggestions. I can’t seem to get any of these solutions to work. It’s a Dell Latitude 520. The manual I found online says to use the Device Select tab in Mouse Properties, but I don’t have that Tab.
Haven’t tried messing with the BIOS. Might have to resort to that.
Splay your arms to the side slightly so they aren’t resting on the touchpad. Now if you rest your wrists/forearms, they hit laptop surface and not the touchpad. Ergonomically speaking, you should have your wrists and forearms in the air anyways.
There is probably a driver/app combo that Dell offers for its mousepad. If these are not installed windows uses a generic driver which won’t allow you to tune and control all the bells and whistles, so you don’t get all the tabs. See if there’s such a download on the Dell website and I bet you’ll see the proper options under “Mouse Properties.”
I tend to have the same problem as the OP, and it’s not the arms or wrists doing the accidental clicking, it’s my thumbs hitting the pad accidentally.
For mine, Settings -> Control Pad -> Mouse and then the Device Settings tab has an option to disable the touchpad. (But not one for my USB mouse Go figure.) I have an HP laptop with the same setup as BarnOwl, and the on/off button still works, but the mouse stays disabled.
ETA: Oh, but in the hardware tab, the properties button for the USB mouse gives me the option to disable it.
Does it happen from just carelessly resting your thumb down, or is it associated with certain keystrokes, ie: whenever you hit space bar, your thumb also hits the touchpad? We must have different laptop layouts, as I’m just having a tough time visualizing how I could accidentally hit the pad with my thumb. For me, I need to turn my hand entirely or stretch my thumb to the side unnaturally to access the touchpad (ie: it takes a deliberate action, I don’t mean to say that I need to contort to access it).
Bizarrely, it’s with the hand I’m not using, when reaching for a number or function key - as one hand stretches, the other moves in the opposite direction. I’ve disabled it via the BIOS, I prefer a mouse anyway.
If you want to semi-permanently disable it, it should be possible in the Device Manager - (in Windows XP) click Start>Run and type Devmgmt.msc - the device manager will open, expand the category ‘human interface devices’, right-click the entry for the trackpad and select ‘disable’