Great answer !
It covers whole matterI asked, although it's a real pity that new (editor/manager) accounts can't be forced to change passwords in backend.
But there's always a way. Routing the user after logging in frontend to a hidden administration panel should be a sufficient method.
I'd like to ask if "Force Password Change" plugin works also in joomla backend ?
I tried several times with creating new accounts, resetting their lastvisitDate value to 0000-00-00 00:00:00 but this plugin doesn't want to launch after logging into backend, while it is working fine in frontend.
I have been searching but did not find any info, so could you shred some light on this matter ?
Might this be a problem with another plugins, that have to be uninstalled instead of only disabling them temporarily ?
ps. J! version I use: 2.5.14