|When you transferred .pst file etc. did you "export" it - which is the usual route. Later (whenever) it can be "imported" into another version/installation of MS Office\Outlook.|
When you do the import the .pst it will likely end up in a separate profile; listed within the User's details. And it is possible to have end up having several "user" profiles showing the same or some of the same data. The assorted profiles are all in the same place. (I'm not a windows system just now, and can't remember where exactly that is...; but a little research on the web, or digging around user profiles and you will find it.)
Also - double check your account details for the new Outlook installation; incoming and outgoing servers; and account login (user name) and password.
The password likely you're seeking is the one used to access/login to the account - which is usually a pop3 or IMAP for most users; occasionally "exchange". Outlook will allow to connect to many web-based emails utilities - but you need to know the online login details (for whichever account) to set up/enable Outlook to access it. If you had one of those (or a similar account) which means you have access to it on the web directly too... then that's the password you need to apply in your new account.
If you don't know the password for the account in question - and presuming it is a web-based one as above - then there is marked reluctance here to go much further. This for the reasons DerbyDad03 mentions... Likewise if it's a password for an email account provided by your isp then you would best contact them?
As you rightly surmise.. there are "utilities" which will dig out a forgotten password; presuming it's thereon the computer in the first place. Google will no doubt bring them up...?
message edited by trvlr