I still get "Invalid request! No data was saved."

[shiruken]

After installing VestaCP, I reinstalled the Roundcube database (per viewtopic.php?t=6346) then forced HTTPS via .htaccess file (per viewtopic.php?t=10054) yet after creating an email account in VestaCP, nothing shows up in the roundcube database's user table, and I still get "Invalid request! No data was saved." ...even when using a:a as username:password (I would expect an error of some sorts)

Any help would be greatly appreciated. Thanks!!