Cannot login since latest upgrade (3 replies)

Hi all,
Since the new upgrade I am no longer able to login to my piwik site.
I have reset the password from the login page, same result.
I have also followed the instructions on the site to reset the password through mysql, no dice.
I double checked and my config.ini.php is the same as before, correct DB entries.

I am running on nginx with varnish cache, have never had a problem previously like this.

Can anyone help?

thanks