.ost and .pst files are confused

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Diplomat Dave

New Toshiba laptop purchased that has Windows 7 installed as operating system. Installed our Office 2003 Standard Edition and all was well.

After a few days of getting used to new computer we switched ISP's from a local Wi-Fi company to the Verizon MiFi "hotspot". In the process of doing that we set up a Hotmail account and used Outlook Connector to splice Outlook 2003 and Hotmail so that we could continue to do mail using Outlook.

The system stopped downloading e-mail and it appears to be because it's going to the .ost file and not the .pst data file. This computer has never been on an Exchange Server so I do not understand how the .ost data file got established in the first place.

That's not to say that I did not inadvertently flip a switch during the process that made it think we wanted an .ost data file.

What can I do to consolidate the old .pst file and the new .ost file and get e-mail to download to Outlook?



Brian Tillman

The Hotmail Connector makes Outlook act like it is connecting to Exchange. The OST is the cache reflecting the contents of the Hotmail folders. Outlook does not download Hotmail Connector-based accounts like it does for POP accounts. If you want downloading to a PST, use a POP account to access your Hotmail mailbox.

Diplomat Dave

Thanks, Brian. Per your suggestion, I tried to set up a POP account but could not determine what to populate the server information fields with. I tried the Hotmail e-mail address but Outlook did not accept that.

I then tried "Additional Server Types" and it offered as the only option, "Microsoft Outlook Hotmail Connector". So I tried that and it did download into the newly established Inbox all that was in the Hotmail website Inbox.

But now I had two identical appearing Hotmail account folder sets in the Folder Pane of Outlook. I tried consolidating the e-mails into one set of folders and deleting what I thought was the redundant Hotmail account, only to lose the newly filed e-mails along with the "duplicate" account.


Thanks again,



The ost file is the hotmail sync file and is perfectly normal.

Are you saying that you aren't receiving Hotmail, or email from some other email account?

Diane Poremsky

Senior Member
Outlook version
Outlook 2016 32 bit
Email Account
Office 365 Exchange

Remove one of the hotmail accounts you created, remove both if you want to use POP3. POP3 config is listed on this page:http://www.slipstick.com/problems/msn_denied.asp

Is there a reason why you don't want an OST? If you use the connector, you'll get an ost file. If you want a pst, you need to use POP3.

Honestly, for hotmail, the connector and the resulting ost is a better experience - you have copies of your mail on the server and in outlook, you'll have hotmail's contacts and calendar (if you use them). You can read your hotmail online (from anywhere!) or in outlook and will see the exact same content both places.

Diplomat Dave

Thanks, Diane, and the rest of the MVP's too.

Through my fumbling attempts to correct this problem I wound up with a bunch of .OST and .PST data files. Fortunately, if I can use that word, there were not many e-mails involved since they were pretty much wiped out in the hard disk crash on the old computer. Setting up a new PC along with a new ISP and moving the mail account from the former ISP to Hotmail just had too many moving parts.

I've uninstalled Office 2003 and reinstalled it and am setting up the Outlook to use the Hotmail account via Connector.

Hope it works, though I am concerned that there seems to be a lot of legacy files like three copies of "Contacts" with no way to differentiate one from the other.

Diane Poremsky

Senior Member
Outlook version
Outlook 2016 32 bit
Email Account
Office 365 Exchange
Is Hotmail your only account now? If so, you can open the old pst files in it and copy the contacts to Hotmail then close the old pst. If you are using your isp account and hotmail you'll have 2 contacts folders. No way to avoid it.

Diplomat Dave

Yes, Hotmail is the only e-mail account now. Think I've got it going now and will update contacts as new ones arise. Not much to salvage from the old .PST files.

Thanks again for all of your help.
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