I only have Excel 2002 available here. You should be able to find the instructions by looking in the System i Access User Guide.
From the PC Start menu, Programs-> IBM System i Accessfor Windows-> User’s Guide.
On the Index tab, type [ excel ] in the input box. A topic should come into the list titled something like “Excel add-ins, installing”.
Follow the instructions from that topic.
Open Excel Program —->Tools —-> Add-ins —-> Browse / C:Program FilesIBMClient AccessSharedcwbtfxla.xll