This looks like a trivial issue but in fact it is not. Sony Vaio, in particular, will not let you disable the touchpad in BIOS or in Device Manager. Most instructions on the web will tell you to "Open Vaio Control Center, expand Mouse and Pointing Device, find checkbox that says Enable and uncheck it..." Well, guess what? It works only when laptop is fresh from the store with all factory default software installed. As soon as you made a clean install of Windows 7, all Vaio software is gone or stops working properly.
This instruction will tell you how to restore Sony Vaio software and bring this "Enable Pointing Device" checkbox back from abyss.
Step 1: Locate Factory Software for Your Sony Vaio Model
Locate your model number (mine is VGN-FW449J/B, I will use it for example since it is a very typical model) and go to Sony eSupport site.
The screenshot shows VGN-FW449J/B page, but you can easily change it by clicking on "change model" link.
Also, select your operation system from the list (see screenshot).
Step 2: Download and Install Multiple Software Components
The number of the components required to see the pesky "Enable" button varies depending on the Sony laptop model, my list was the following (see screenshots):
- Intel Chipset Driver
- Setting Utility Series
- VAIO Launcher Software
- VAIO Control Client Software
- Alps Pointing Device Driver
- Sony Firmware Extension Parser Device Driver
- Sony Shared Library
- Update: Sony Firmware Extension Parser Device Driver
- VAIO Event Service
- ATI Graphics Driver
- UPDATE: Vaio Event Service Update
Well, I am not sure if ATI Graphics update is really needed for our task, but it's good to install it as it enables keyboard hotkeys to change screen brightness. Try changing screen brightness without those hotkeys (Fn-F5 and Fn-F6) on Sony Vaio laptop... and you may start feeling really stressed.
Selected software components can be installed in any order, you just need to make sure you install them all.
Step 3: Restart Your Laptop and Observe the Checkbox
When all components are installed and laptop was restarted, you can finally open the "Vaio Control Center", expand "Keyboard and Mouse", go to "Pointing Device" and uncheck the "Enable" checkbox. Hooray!
Now think of one more thing: how easy would it be for laptop manufacturers to implement the following feature: "plug external mouse > disable touchpad, unplug external mouse > enable touchpad"... Easy?