Here is what I see on my Desktop HP Pavilion a152On

Microsoft Office Standard Edition 2003
Installation Error; File not Found

A required installation file O0561401.CAB could not be found.

Original Installation Source Required
It Says I need which ever installtion source that was used originally needs to be reinstalled.
However I do not have any original CD's as source nor do I know find it on my PC.
Anyone able to advice me to correct this issue?
Thank You