"Could not open database" after Win 7 MySQL install (no replies)

Hi,

I am running on: Win 7; workbench 5.2.40 R 8790. This is part of the MySQL download installer. This is a "Developer" install.

I have just been through an uncomfortable install process for the combined Mysql server, connectors and workbench on Win 7. I have had to re-install many, many times before i had what I think was a clean result.

I have started workbench. I see the default connection and I can enter the "Server Administration" portion. I can run the command-line mysql client specifying the user "root" and the password I assigned. I can not, however, "Open a connection". I get the message [from the wb log]:

12:35:07 [ERR][      WBContext]: Your connection attempt failed for user 'root' from your host to server at 127.0.0.1:3306:
  Could not open database

Please:
1 Check that mysql is running on server 127.0.0.1
2 Check that mysql is running on port 3306 (note: 3306 is the default, but this can be changed)
3 Check the root has rights to connect to 127.0.0.1 from your address (mysql rights define what clients can connect to the server and from which machines) 
4 Make sure you are both providing a password if needed and using the correct password for 127.0.0.1 connecting from the host address you're connecting from

I have seen a few suggestions on-line. I have re-installed *everything* a couple more times. I have removed the workbench password file. As above: I can connect using the command-line mysql client. The server is running.

Ideas?