"Orphaned" OST file due to removing hotmail profile from Outlook account settings.

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Hi Everyone,

I have a unique problem here and i wonder if someone can offer me a solution.

Last week, i used Windows Outlook Connector v14.0 to sync my hotmail account (e.gxxx@hotmail.com) with Outlook 2010. It went well and my mails from my hotmail account were all " downloaded" into my Outlook.

However, i went to clean out all my mails from hotmail and unknowingly when i reopened my outlook, it started to sync with hotmail and began clearing out my mails in Outlook as well. This was when i immediately stopped the synchronisation process and went on to remove the Hotmail Profile (which was connected via MAPI settings) from my account settings in Outlook. When i did this, all the folders in my outlook closed, and i am left with an" orphaned" OST file.

I tried several times to reconnect with Outlook Connector but each time, it created a new OST file (e.g hotmail0.ost) and cant sync back with the original OST file. Hence, i can't access my emails on outlook now. And these same emails previously on my hotmail account has already been deleted from the account as well.

I now have 4 years worth of emails in my OST file (770mb) and i can't open it with Outlook 2010. I understand there isnt such a function within Outlook to open or convert an OST file and require a 3rd party software to convert OST to PST file. These 3rd party softwares are exorbitant and their demos dont work too well.

Is there anyway i can reconnect my original OST file with the Windows Outlook Connector and " reverse" sync it with my hotmail account so that my emails can be " revived" . Or is there anyway i can open my OST file with Outlook or other softwares?

Thank you so much for your help.



Diane Poremsky

Senior Member
Outlook version
Outlook 2016 32 bit
Email Account
Office 365 Exchange
You can try using system restore to drop back to before you deleted the hotmail account from the profile - then disconnect from the internet and open outlook. Hotmail can't go online so it can't sync - you will need to move all the mail to a local pst before going online or it will be deleted from the ost. If you need the mail online, you can move it back to the hotmail folder after the first sync.

This is specific for Exchange accounts but the process is the same for Hotmail:http://www.slipstick.com/problems/pst-repair/convert-an-exchange-offline-file-ost-to-a-personal-file-pst/

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