Reply To: Unable to import .ost file to Office 365
Eddie Thwan ~
Modified: February 21st, 2017 ~ ~ 1 Minute Reading
Hello Barry,
I am sorry for your old ost data loss.
This happened might be because OST files are encrypted with a unique key derived from the mailbox’s unique entry and also Microsoft doesn’t support changing the OST file directly.
Maybe you can try and see if you still have the profile from which the OST file was generated. If the profile still exists, then copy the ost file to that profile and try to recover the data.
This will also resolve your issue to transfer OST to Office 365 account.
Please feel free to ask if you face any further issues or any other issues related to Office 365.
Thank you.
Eddie