Try using the IBM DB2 for I IBMDA400 OLEDB Provider included with IBM I Access.
I tested it briefly with Excel 2010 and it worked perfectly. The driver can be installed directly from the IBM i system using the UNC path \\system\QIBM\ProdData\Access\Windows\cwblaunch.exe.
How to configure the Microsoft OLE DB Provider for DB2 to connect to an IBM I (AS/400)
PROVIDER
CONNECTION
DATA SOURCE
The optional Data source parameter names the Universal Data Link (UDL) file in the settings are saved.
NETWORK
The Network parameter must be TCP/IP Connection. You must click the ellipsis and configure the IP address of the IBM.
SECURITY
The Security parameters are self-explanatory.
DATABASE
The Initial Catalog parameter refers to the relational database name configured on the AS/400 system. It can be found with the DSPRDBDIRE command from a terminal session. The default is the system name (serial number) or RCHASE12.
The Package Collection is the name of a library where temporary objects required by the Microsoft OLE DB Provider for DB2 will be created.
The Default schema is the name of the default library for unqualified objects.
ADVANCED
DBMS Platform
Select DB2/AS400.
TEST