Invalid Login Parameters after clean install

So i've been trying to get this working for about 10 hours and not getting anywhere. Followed the instructions to the letter (as best as possible considering i'm running it on Windows/IIS with PHP), but i always get the Invalid Login Parameters error.
All modules are loaded, settings changed in the PHP.ini file, no problems with MySql (tables are populated and working).
The whole system has been wiped clean and loaded from scratch and it gives the same error.
Tried resetting the password for the admin user with the SQL commands but this made no difference.
The logs are clean and only show the login failure, iis logs don't show anything useful so i didn't include them.
Attached are screenshots of my latest attempt and it fails at first logon. Any advice on what i'm doing wrong would be appreciated.
(the max_input_vars warning on the 2nd image is wrong as the value is currently set at 4000)

Dropped all tables and reconfigured but same result
Uninstalled MySql and deleted all files manually, reinstalled and the same result.
Not sure what difference it makes but i reinstalled MySql again using the full install and now Projeqtor is working fine - not sure why it didn't like the Server/Developer install modes. (i used the full MySql package and the built-in installer).
Thanks,