How to delete multiple same emails in 'large mail' folder

[Tasaror]

My harddrive was formatted. I TRIED to reload all .pst archived emails.
Outlook does not want to import & export all - says 'not a .pst folder'.
Those I have reloaded have multiplied and duplicated up to 250 times per
email of the same email. My Large Iems and Unread Items show duplicates as
above - same problem. Must I delete ALL? 2) My address book has disappeared.
All contacts are lost. Where are they? 3)There is a period of 4 days received
email missing on Outlook - where are they? After formatting and between
re-installation of MS Office Student I received important mail - this is the
mail that has disappeared. Microsoft also downloaded updates and service pack
3 at this time - does this have something to do with it? 4) MS automatically
archived yesterday - this function is OFF on my machine - size of archive is
over 7 gig. What can I do to repair all? 5) Restore to earlier date does not
want to function. 6)When I click on the 'Go' in Outlook & then 'Folders"
nothing happens. 7) I am NOT a computer expert or boffin, so PLEASE explain
in plain English. Please help!

 

[DL]

And what version of Outlook is this?
MS Office H&S doesnt neccessarily include Outlook
You dont Import native outlook data, within outlook you browse to and open
the pst
The pst should be located on the hard disk (ideally) in eg Documents folder,
the read only flag should be off (properties of the file, as seen in
Explorer)
A restore has no impact on data files