Plp For Matlab R2007b I Want Install Software MATlab But It's Asking PLP(personal Licence Password) While Installing.?

I want install software MATlab but it's asking PLP(personal licence password) while installing.? - plp for matlab r2007b

asks me to contain www.mathworks.com to the number of PLP, which I did, but I do not know how to get this number and get to the installation. VLSI design and install on my PC. There is also a problem of obtaining license .. pls help me how to solve it.