Did you try doing a repair of the Office/Outlook 2003 product via add/remove
programs?

The only other question I can think of is to ask is, are you using a
shortcut you created yourself to start the program? (e.g. Do you get the
same error by start Outlook by selecting Start Run Type: outlook.exe
OK button?)

"boysie" wrote in message
...
Recently had to replace motherboard, so due to not wanting to pay HP "fee"
to
re tattoo BIOS, reloaded OS (Windows XP). Saved previous content of hard
drive on external hard drive.
Reloaded Office 2003, now cannot get Outlook to recognise old .pst files
from previous content of hard drive. When I attempt to open a .pst file,
get
error notice "Cannot start Microsoft Office Outlook. The command line is
not
valid. Verify the switch you are using"
Grateful for any help.
--
Boysie