Many AS/400 customers have struggled with keeping current on technology and attempted to integrate the PC and its technology with the power of the IBM platform.  It is already a known fact that older versions of the IBM operating system (OS) have compatibility issues with new peripherals, but an issue with even more concern recently is compatibility with newer releases of Microsoft products.  

This is especially true of Microsoft Office 2007 XP, which has different requirements depending on the AS/400 operating system that is in place.  For example, if version V5R3 is the OS, you must have V5R4 of Client Access installed to insure proper operation of that package.  With the most recent version of the OS V5R4, the Client Access update can be downloaded directly by the user. 

When considering the purchase of new PCs and laptops, it must be understood that the resident Microsoft operating system is likely to be Vista, which opens another can of worms.  Only OS version V5R4 has provisions for accommodating Vista, and that is for the Business Edition only.  So when the acquisition of new PCs or laptops is being considered, the version of Vista bundled with the hardware must be confirmed with V5R3.

More details on the integration of Windows and the AS/400 platform can be found in the white paper titled "Integrating PCs and AS/400 Systems" on the Microsoft website.