Simply download the driver from ibm site for National Semiconductor Trusted Platform Module (TPM) download.lenovo.com/ibmdl/pub/pc/pccbbs/thinkcentre_drivers/q1tpm02us13.exe
run the file, it will be extracted to c:\swtools\driver\NSCTPMDriver\q1tpm02us13 meanwhile an error message will be shown ignore it and run setup from given path and it will do the rest.
I have just installed it in windows 7 ultimate. This driver is for windows XP but works in windows 7 as I have told you the way.