where can I find application to open Outlook pst files

[KJV]

I want to open the archive.pst file but I get a message saying the following:

"You are attempting to open a file of type 'Office Data File' (.pst)
These files are used by the operating system and by various programs.
Editing or modifying them could damage your system.
If you still want to open the file, click Open With, otherwise, click Cancel."

Problem: Of course I want to open the files as these contain (allegedly) my
"archived" e-mails. Why would I choose to archive e-mails where they cannot
be retrieved? The archiving is initiated and implemented by Outlook. Please
help.

 

[JR Hester]

Are you opening the archive from within Outlook? File>OPen>Personal foldes
file(pst). The message you quote wouyld typically appear when attempting to
open the archive files from outside of teh Outlook application.

 

[SW]

I too, am unable to open my .pst files. From within Outlook, I am clicking
on File>Open>Personal Folders File (pst) and that does take me to my three
..pst files: archive (558 MB); outlook (1.62GB); backupContacts.old (3.34 MB).
When I try to open any of the 3 pst files, it says 0 Items in the bottom
left hand corner of my screen. Any suggestions on what I should do to be
able to access all that I archived in my Personal Folders File (pst) ?
Thank you,
SW