my $dbh = DBI->connect('dbi:ODBC:SQLSERVER', 'user', 'pass');

##</code><code>##

DBI connect('SQLSERVER','user',...) failed: [Microsoft][ODBC SQL Server Driver][
TCP/IP Sockets]SQL Server does not exist or access denied. (SQL-08001)
[Microsoft][ODBC SQL Server Driver][TCP/IP Sockets]ConnectionOpen (Connect()). (
SQL-01000)(DBD: db_login/SQLConnect err=-1) at db_config.pl line 16