I am having a Xp laptop running with MS Office 2003. It was working fine without any problem since months but suddenly I when I tried opening a Excel file today morning it refused with an error message stating “PRO.MSI file is missing”. I have heard about this file for the first time today. It says to insert me the installation disc in order to fix it but the problem is am not carrying the disc along with me now. Cany anyone tell me some alternate of fixing this ?