If you're using mssql express, you need to add \SQLEXPRESS
to your database address/ip, so in your example you would use Server=(local\SQLEXPRESS)
You're using an odbc connection string. OLEDB or native client strings are the preferred method eg
SQL_Conn_STRING = "Provider=sqloledb;Data Source=local\SQLEXPRESS;Initial Catalog=classic_asp_poc;User Id=my-domain\username;Password=my password"
See this easy to remember link for more examples