> I would like to use different contact folders / files, containing
> information for different companies, and i do not want to get the
> names mixed in one singel file.
You can create and use as many contacts folders as you wish. They can be in
the same PST or in different PSTs, as you see fit.
> Is it possible to use different "adressbooks (= contact files) in
> outlook 2000?
Sure. As you create your extra contacts folders, enable each one as an
address book.
> I want to export one .pst file from one system (PC) and import it to
> another but not mix or overwrite the information in target machine.
Don't export or import. Create a new PST (File>New>Personal Folders File).
Create a new contacts folder in that PST (File>New>Folder. Specify that it
contains Contact items). Populate it as you wish. Close Outlook. Copy the
PST to the other PC by any means yuo wish, placing the PST in any folder on
that PC you wish, making sure you do not overwrite an PST of the same name
when you do. Make sure the PST is not read-only (right-click and choose
Properties). Now start Outlook and open that PST with File>Open>Personal
Folders File. You'll now have access to the contacts folder it contains.
Enable the folder as an address book and it will be available for choosing
when you're addressing messages.

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Brian Tillman