My brother has just brought me his laptop to look at after forgetting the login password. It was frequently asking him to change the password, and one day he changed it and then forgot it. I found a simple command to stop the password from expiring:
First run Cmd (Command Line) as Administrator (click Start -> and type cmd. Right click on Cmd and choose “Run As Administrator”). If you followed correctly this should give you a black command line window with white text.
net accounts /maxpwage:unlimited
And press return or enter.
It should congratulate you, or say successful (can’t remember the exact wording).
The password should then last forever, or until it is changed manually.
Note: It is good practice to change passwords regularly, however outside of corporate IT land can be a huge hassle. Just ask my brother 🙂