Try having a look at this it might help http://office.microsoft.com/en-ca/powerpoint-help/locate-missing-msi-files-HA001118572.aspx?redir=0
I also found this item that might help
Have you tried repairing your installation?
1. Click Start, and then click Control Panel.
2. Click Add or Remove Programs.
3. Click the Office program that you want to repair, and then click Change.
4. In the Maintenance Mode Options dialog box, click Reinstall or Repair, and then click Next.
5. In the Reinstall or Repair Office dialog box, click Detect and Repair errors in my Office
installation, and then click Install.
6. When the repair process is finished, run the update again.
Most likely you will need to have your Office 2003 CD handy.
MS Office Download Page http://office.microsoft.com/en-au/of...e/default.aspx