phpbb2 convert access error

[tibet]

hi,
i want convert my forum phpbb2011 to smf
but i have a little problem 
smf.php make error :

Sorry, the database connection information used in the specified installation of SMF cannot access the installation of phpBB2. This may either mean that the installation doesn't exist, or that the MySQL account used does not have permissions to access it.

i dont know sql so much
what can i do for this error ?

[Oldiesmann]

That means that the MySQL user you assigned to the database SMF is running on doesn't have permission to access the database that phpBB is running on, so you need to assign that user to the phpBB database as well.