get the latest version of that pst-file from your backup, and import those missing folders from there to your current Outlook-database (using File>Import).
If you don't have a backup, you've lost your data. That's one of the rules of the game: you will (sooner or later) lose what you don't backup.
By the way: what do you mean with ''I was only prompted to delete that certain folder''. I never saw a prompt/request to delete a folder in Outlook. I just select the folder, and then use either right-click + delete or the delete-key. Both of these operations move the whole folder to the Deleted Items folder, and I can move them back as long as I didn't close Outlook.
Can you explain that?
Kees
I have microsoft outlook 2003 and I normally create folders for certian -emails. Two days ago, i deleted one of the folder and with it went some other folders. Now I cannot retrieve the other folders and dont know how they gor deleted when I was only prompted to delete that certain folder. can anyone help.

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