Sorry , I thought I had figured out the problem but instead keeps coming back to various users .
Use HFS 2.3 g 295 version , with a view template Themes Full , when users ( all part of the group "can change password " ) when they log in with personal credentials , and try to change their password , password change window appears with input box new password and repeat password , pressing the button changes , but appears white window reading " Forbidden " .
I tried to reset the default template and the regular password changes work .
Obviously in the template View Full Themes is "on" button to change password .
Why , what should I do ? It happens with both Internet Explorer ( 9,10,11 ) and Chrome .