How to Open a .PST file from the new outlook. File menu disapeared

I am somewhat back to normal. A while ago gmail said it would stop working with less secure apps like Outlook pre 2013 using POP. We upgraded to Outlook 2021 which used IMAP. I map using a ost format rather then POP. All well and good but or file history was in a pst file so I lost a lot of old documents. Since I changed to Outlook 2021 I could go back to POP. The delema was I need to choose, recent stuff on ost or old files (but importand files ) on pst.

I was looking for Microsoft help in transisioning but nada. So I decided the pst was more important then the ost.

I still have the ost file (which you cannot access outside Outlook, hoping someday Microsoft would accomidate old customers. Guess not.

Ed

SaaS is where the money is, hence, Microsoft crapifying Outlook so that the web app doesn't look as simplistic.

I use an Archive.pst file stored on a removable disk which I carry or store in a safe place when away from my laptop. I have "Quick Steps" programmed to move mail in one click to folders in the PST such as Family History, Financial Archive, Archived bills, etc. Does anyone know how I can replicate these functions when they finally force me off my windows version of outlook. Or at least retrieve the last 35 years of history. And yes, I have had email since 1979.

I have old backed up emails in .pst format but I cant seem to be able to read them anymore in outlook on a new computer. I had saved the mails from old computer as .pst files and I see them in the outlook express but if I try to open them or even click on the backup folder, I get a error message:

"The set of folders cannot be opened. The server is not available. Contact your administrator if this continues "

What is the meaning of this message ? How do I get past it and read my old mails saved as .pst files from old computer ?