Hi,
I had this same problem when installing to a Linux distro (SLES). To resolve the issue I used the following procedure:
1) On existing MySQL instance create a new database called 'alfresco', create a new user (I also called it 'alfresco') and grant all privileges
2) Run default install binary and select advanced method
3) Amend the database properties as required (user, password and database)
4) Accept remaining default options and proceed with the install
5) Once installed open a terminal window and cd to the Alfresco installation location
6) Start the alfresco services if not already running using alfresco.sh start
7) Check the alfresco.log for progress. It does take a little bit of time to build the tables, etc
In your case I suggest the key is step 1 of the above process. Without this the database is not created or populated leading to all sorts of errors including not being able to login to the site.
Hope this helps - good luck…
Regards Peter