Add to Chrome.
Click 'Add extension' above.
The installation process should take less than a minute.
Next, you'll Create an Account.
You might also find your answer in the LastPass Enterprise Manual.
What should the user do if his or her existing password does not match the Windows password?
The user will need to login to LastPass using their existing LastPass password, go to Account Settings, and change the master password to match the Windows login password.