Can not log into 2015 env to run 2012 upgrade

Hi,
So we have vrd 2012. I have got a new SQL DB and created a new 2015 environment. I can go through the wizard and add the new DB and it says "Connection check successful."

Then I press OK and click next. then highlight and connect. Then on the 2015 login to.. screen I can see my new environment but when I click on Login it says

Connection could not be established. A connection to your current environment could not be establish. Please select another one.


What do I do? The DB is empty I need to run the upgrade but I cant login.

Please advise?

Thanks