i once did that while taking apart my other toshiba
i have no idea how the x300 is constructed but in my old satellite to get the top lid off you need to disconnect a flat "cable" from the motherboard that powers and connects the touchpad

if you have done so it is possible that you misplaced this cable inserting the cable underneath the socket instead of in the socket - its really easy not to notice and then take apart your computer again in anger

if this was the case remember there are two clips on both sides of the sockets that lock the cable in
before inserting the cable inside you should pull them towards you, then put the cable in as deep as possible and while applying pressure, so it doesnt slide out, lock the clips

if this wasnt the case im sorry :P

I dont know how to help you. All we can say here is that you must check tochpad cables connection and be sure all three touch pad flat cables are connected properly to the touch pad board.

here is the best i could find for you

http://www.ifixit.com/Guide/Installing-PowerBook-G4-Aluminum-17-Inch-1-1-67-GHz-SuperDrive/248/2

i know its a mac but same rules apply. im almost certainly sure you didnt connect ur touchpad properly, unless you managed to snap the cable at some point

if you want to continue search use such keywords as touchpad ribbon cable or touchpad flex cable

maybe you should do some more research and get back to us when you have sufficient information on your problem, which would save you and us some time

Hi aloushi

Just one question: has touchpad worked before you disassembled the notebook?

I think you have done something wrong during the disassembling procedure which would affect the touchpad functionality.
Furthermore the touchpad should work even if the sysnaptics driver has not been installed. The Win 7 contains the standard touchpad driver which would allow using the touchpad without an installation of special drivers.

Question 2: did you check if BIOS contains an touchpad settings which enabled and disabled this pointing device? Check this… to enter the BIOS press F2 while booting up the unit… I think pressing F9 would set the BIOS to default.

Well, you asked where you could purchase a new touchpad part…well, you can purchase this from Toshiba ASP (service partner) in your country.

Hi,again today i get shocked when i realised that evry time i start my windows the touch pad works for 1 secong moves and stopes evrytime i restart my system,now what could it be !!!!

Hi, yes exactly except the FN buttons they are not working in WINDOWS-7 even thought i installed VAP and config...Etc