Good old FTP and flat file import will do the trick reliably and never take a day off. Here are the basic steps to automate an FTP download in Windows followed by a CSV insert into MS SQL Server.

We use linked servers in SQL Server 2000 (I know...) to pump data from an AS400 running DB2 in to some tables in SQL Server to do analysis. It is realy painful as the source system is a Danish ERP ...