Check out the SMF Function DB!
Sorry, the database connection information used in the specified installation of SMF cannot access the installation of phpBB3. This may either mean that the installation doesn't exist, or that the Database account used does not have permissions to access it.The error that was received from the Database was: SELECT command denied to user 'XXX'@'localhost' for table 'phpbb_users'
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by: 10.0.100.135 (10.0.100.113)