If you only have an OST file and need to access your emails in Office 365, you'll first need to convert the OST to a PST file. Office 365 doesn't support OST files directly. The easiest way is to use a trusted Aryson OST to PST converter tool. Once converted, you can import the PST file into your Office 365 account using Outlook. This lets you view and manage your old emails in the cloud. It's a simple and safe method, especially if you no longer have access to the original Outlook profile or Exchange account linked to the OST.
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What should I do if I only have an OST file and need Office 365 access?
Re: What should I do if I only have an OST file and need Office 365 access?
Try TrustVare OST to Office 365 Converter to convert OST to Office 365 files in bulk. The software can export OST to Office 365 in just a few simple clicks. It has a dual mode that enables you to export single or multiple OST files in one go. It preserves all email attributes and the original structure of emails during OST to Office 365 conversion. You can even choose selected emails from OST file for exporting them into Office 365 format. Download its free demo edition to check its working procedure without any cost. Refer: https://www.trustvare.com/ost/office-365/
Re: What should I do if I only have an OST file and need Office 365 access?
If you are looking for the conversion of OST to Office 365 than there is the best solution available to convert the OST to Microsoft Office 365 by using the OST Converter. It helps you to convert the Outlook Offline mailbox items with attachments into Office 365 cloud account. It is an advanced utility, which can make your task so simple without any issue.