I wasn't able to get back to this until now, but I have verifed that the user has permissions to the database. I tried removing the user and recreating using the same user name and I have tried creating a new user with a different name. Still getting the same error when I get to Step 6 in the install:

UBB Error We encountered a problem. The reason reported was
Script:
Line#:
SQL Error: Access denied for user 'ubbthreads'@'localhost' (using password: YES)
SQL Error #: 1045
Query: Unable to connect to the database!

Everything appears to me to be correct so I'm not sure what to look at now.