If your outlook ".pst" file requests that you run the inbox repair tool you will need to locate it. It can be found in the following locations.
On Microsoft Windows NT and Microsoft Windows 2000 machinesthe file is located at: C:\Program Files\Common Files\System\Mapi\1033\NT
On Microsoft Windows 95 and Microsoft Windows 98 machines the file is located at: C:\Program Files\Common Files\System\Mapi\1033\95
for more information see this microsoft article
Hope this helps
Thanks M.