It depends from user position.

If your account is a manager (Administrator, Network Director, Sr. Affiliate Manager, Sr. Advertiser Manager, Affiliate Manager, Advertiser Manager), you can change the password with these several steps:

1. Login under Admin or Network Director. Open Tools->Managers (see picture A)

Press Edit Button and after that you will see Edit Manager form (see picture B)

Fill Password field and Confirm password field and press Update button at the bottom of the form. Password changed.