DBIx::Class::Storage::DBI::catch {...} (): DBI Connection failed: Access denied for user 'koha_library'@'localhost' (using password: YES) at /usr/share/perl5/DBIx/Class/Storage/DBI.pm line 1520. at /usr/share/koha/lib/Koha/Database.pm line 107
Hi Leena, there is not enough information on this bug report in order to help you und it looks like a configuration/installation issue, as Koha is not able to connect to your database. Please ask on the mailing list instead and tell us the steps that led to this error.