Major issue after password reset

Hi there,

I installed and used this plugin when the Heartbleed issue was announced about a month ago. Since then, a few of my WordPress administrators (but, interestingly, not all of them) and ALL of my regular members haven’t been able to log into my system. I have tried uninstalling the plugin; I have tried manually setting new passwords for users; I have tried having users use the ‘Lost password’ function. None of those options have allowed these users to log in.

I’m not sure if the fault was caused by this plugin or not, but I don’t really know where to begin to try and figure out what the cause is.

Could you please advise how I should proceed with this?

Thank you in advance for your help,
David

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