SOLVED I have WIN10,Outlook 2010.

[George Cucak]

I changed my outlook account to an account with a new email address. In the process I somehow ended up with a data file holding
my emails that ends with a ".ost" extension instead of .pst. I didn't know this until some time later.
Is there a way to fix this so the emails can be kept in the .pst data file and not in a hidden App file under my user folder?

Thanks for any advice on this.
George

 

[Trouble]

A PST file is generally the result of configuring your email account as POP3 / SMTP rather than an Exchange / ActiveSync account.
To do this use the Control Panel applet titled "Mail (Microsoft Outlook) and choose to manually configure the settings.

A .pst file will automatically be configure as part of this task.
Possibly more important.... IF you have an existing PST file from a previous configuration of Outlook on the same machine you will want to point outlook at the existing file during your configuration steps, so as to preserve your old emails, calendar(s) and contacts (people), during the advanced steps of the configuration process.

 

[George Cucak]

Trouble....thank you for the quick response.
Unfortunately I don't think I have the expertise to execute the fix you suggest.
For instance, an important item you point out (IF you have an existing PST file from a previous configuration of Outlook )
is a problem for me. One is an old Road runner file and the other is an .ost file. See attach.
I don't think I want to point to either one, plus I don't know the ramifications of doing otherwise.
I'll just live with what I've got for now.
Thanks again for your time and effort.

 

[Saltgrass]

One thing to note about your attachment is one is normal e-mail whatever that is called and one HotMail account. Those accounts have different extensions. I don't use HotMail and have no .ost files.

I get really confused by the types of e-mail and properties of each. But when I changed mine over to IMAP types I had to change the server ports used by the ISP. I have to go back and read explanations such as the link to remember how they work.

What are IMAP and POP? - Microsoft Support

Learn the difference between IMAP and POP, and when to use each one.

support.office.com

 

[Trouble]

Good link @Saltgrass
The important take away, I think, is that nothing in most instances, precludes you from configuring your email as either or both.
Gmail, Hotmail, Outlook and many others can generally all be configured as POP3 accounts and use a PST file for local storage and access.

Personally, I've never understood the value of setting up IMAP locally.
IF you're going to use web based email, why not just use browser access consistently across the board and leave it at that.
The true value of an IMAP account, like the article you linked to says is, the ability to access your email from any place in the world on any device at hand.

I can see real value in that for some people unless your internet is down or for some reason your provider's mail server is down and you really need to see that email you got yesterday regarding a collaboration you're working on for a critical project.

I have a friend who uses his Gmail account exclusively as IMAP / Web mail and has literally decades of email stored there.
I on the other hand, have my Gmail account configured as POP3 and don't mind the responsibility of archiving (backing up) the associated
PST file locally from time to time.
AND
I don't particularly like the idea of having my personal email stored by someone else, somewhere else and relying on them to keep it safe and secure from potential malicious actors.

 

[George Cucak]

Trouble and Saltgrass…thank you very much for the 'IMAP and POP' link
and the your rationale of using one or the other. The link and the analysis of
using IMAP/POP really cleared up a lot of questions for me.
What bothers me most is this ‘.ost ‘ file is not sitting in my Outlook folder like
the .pst files and therefore not in my file history backup.

Thank you both for enlightening me.
George

 

[Saltgrass]

Something else you might do it look up the meaning of an ".ost file extension". It seems they are created my Outlook 2005 and later and can be larger than .pst files. You will also see software which can convert .ost to .pst.

If you look up .pst you may find software which will convert .pst to .ost....

The following quote from the link above may help and make note the comment about attachments may or may not be downloaded.

IMAP only downloads a message when you click on it, and attachments aren't automatically downloaded. This way you're able to check your messages a lot more quickly than POP.