The "Regain SE Account" plug-in has now been disabled : (
We're sorry, but we had to disable it to avoid being called as a phishing site, as discussed for example here.
But don't worry, you can still regain your account!
SE users can still regain their account. Please refer to the update regain account page.
So, a sad, apolegetic farewell to the "Regain SE Account plugin", and apologies to polarkernel who spent so much time making the plug-in.