Mr Belvedere's suggestion is correct.
With Notebooks / Laptops the built-in peripherals are usually (for want of a better description) implemented differently and therefore the standard operating system built-in driver often does not work. You need the Toshiba Tecra <model-number> drivers for WinXP. You may also find that things like display, audio and built-in pointing devices will work better or have more features (or sometimes just work).
Your issue is a common one when an operating system upgrade for a Notebook / Laptop is not sourced from the OEM (Original Equipment Manufacturer).