I hope someone can help me with this weird problem
My laptop is Satellite U405-S2833 with 1.2 GB Core 2 duo.

It came with a Vista home premium operating system, but I later added XP professional to it (Dual booting)
About 10 months ago, the touchpad as well as the 3 USB ports stopped functioning. Two of the ports will not recognize peripherals, but could power the items, while the third was totally redundant. Since then, I have been using an express card USB adapter for attaching an external mouse and other peripherals. The problems were occurring in both operating systems.
Laptop technicians have had a look at it to no avail.

Here comes the weird part: On occasions when I had to repair or install windows, the pad works perfectly, only to stop working after windows has fully installed.

NB: I have updated the BIOS to the latest version (4.0). Windows 7 RC also exhibited the same problem

go to the Toshiba site and get the latest drivers and utilities

I have tried that to no avail

So the problem has occurs now on XP, Vista and Win 7??

1) Try reinstalling the USB controllers AND the motherboard chipset. NOTE THE ORDER IS IMPORTANT See How to Reinstall Your USB Controllers and Motherboard Chipset Drivers

2) This is a longshot (but can't hurt). Remove your battery and unplug the laptop for about 10 minutes.

Thanks.
Going through the BIOS setup, I discovered that "all pointing devices" had been disabled. I enabled this and the touchpad started working.
I then followed to the letter, the instructions on reinstalling USB Motherboard Chipstet drivers". But the USB problem persisted.
Guess its an hardware problem.
Many thanks to everyone who chipped in with suggestions.