the error part Object required: '' tells us that the connection is not being made to the database, as there is an object required - ie the database - so that is where the error is.
objConn.ConnectionString = "DSN = userinfo.dsn" will be the line that is upsetting your code.
http://www.connectionstrings.com/ is a page that will show you different connections strings depending on your database and not using DSN which does make things easier. There are also sample DSN connection strings.
set objConn = Server.CreateObject("ADODB.Connection")
'objConn.ConnectionString = "DSN = userinfo.dsn" ' comment out this and try the line below
objConn.Open("userinfo") ' if userinfo is the name of your DSN connection else put the name of your DSN in place of userinfo in the string
'objConn.Open ' comment out this one as it is in the above line