This is suppposed to change your dynamic ip

In notebook type
ipconfig /flushdns
ipconfig /refresh
ipconfig /renew

then save as (select all file types) ---filename.bat

this is now a batch file rather than a txt file simply hit run on the file and watch the progress.

If you want to print out the result add this line into the same file befoe "END"

ipconfig /all>filename.txt

a report will be saved in the same directory as your batch file detailing your new ip and a bit more