Log into WinSPC as an administrator user that has permissions to edit the user.
In the "Users" tree of the WinSPC administrator window, find the user that you want to modify.
Double click on the user (or right-click and choose "Properties"). This will open the "User Setup" window.
Click on the "Password" tab.
Fill in the "New Password" and "Confirm New Password" fields with the password you want to set for this user. If a "Password Mask" has been defined, then the password will need to conform to this set of rules.
Click on the "Change" button to change the password.