If you want to access any password protect computer  with the help of USB stick.    follow steps 
Download UBUNTU OS
Click here to DOWNLOAD

Then install ubuntu in usb stick
 1.Insert a USB stick with at least 2GB of free space
 2.  Download the Universal USB Installer 
 3. Click 'Run' when prompted










4.If the security dialog appears, confirm by clicking 'Run'









5.Read the licence agreement and choose 'I Agree' to continue












6.Select Ubuntu Desktop Edition from the dropdown list













7.Click 'Browse' and open the downloaded ISO file














8.Choose the USB drive and click 'Create'













After installation restart computer and go bios and select unable boot from usb.
then you can access computer and all data...