EdbMails OST to PST converter

Yes — you can open an OST file in EdbMails without Outlook installed. That said, if the goal is converting the mailbox and folders to PST, Outlook needs to be on the system. If you're heading straight to Microsoft 365 or Exchange instead, Outlook isn't required at all.

Converting OST to PST makes sense in a number of situations, and EdbMails OST to PST converter handles each of them:

• Corruption of OST file: When an OST file goes corrupt — Outlook crashes, hardware failure, that kind of thing — EdbMails recovers the data and converts the file to PST, getting you back to your email.
• Switching email clients: When you're moving off Outlook to a different client, EdbMails converts the OST to PST so the data travels with you in a format the new client can actually use.
• Access to emails when Exchange server is disconnected: If Outlook can't reach the Exchange server, EdbMails converts the OST to PST so the data stays accessible locally on your device.
• Upgrading to a new version of Outlook: Older OST files and newer Outlook versions don't always get along. EdbMails sidesteps the compatibility gap by converting the OST into PST, which the new Outlook reads without complaint — emails sync in, and the upgrade carries on.
• Outlook inbox fails to update: Sometimes the inbox just stops pulling new mail, or the Exchange mailbox goes temporarily unreachable. When that happens, EdbMails OST to PST converter pulls the OST data into a PST so you've got access to the mailbox content while you sort out what's actually wrong on the server side.
• Backup and archiving: Running an OST to PST conversion gives you a backup of the mailbox data — handy for long-term archives, and the kind of thing you're glad to have around when disaster recovery comes up.

 See how to save Outlook emails to a hard drive.

Yes — EdbMails imports the full payload from OST to Office 365: emails, attachments, calendars, contacts, and the rest. A few clicks gets the entire mailbox to Exchange Online. Connection security to Office 365 runs through modern authentication, which keeps the sign-in safe.

 Steps to import OST to Office 365

To recover and convert deleted mail items or folders, pick the OST file in EdbMails, expand the relevant mailbox, and head into Recoverable Items >> Deletions. If you're trying to export a folder that was deleted from the OST to PST, pick a backup snapshot of the source file from before the deletion happened, then run the conversion from there.

 Steps to recover and convert deleted mail items from an Outlook OST file

Errors like 'Outlook OST cannot be opened', ‘Outlook profile.ost is in use’, and 'Errors have been detected in the file outlook.ost' all clear up the same way — convert the inaccessible OST to PST. Going through PST gets you back to your mail data when the OST is corrupt or won't open. EdbMails OST to PST converter handles the recovery and export, restoring the data so it's usable again. The same OST can also migrate directly to Office 365 or live Exchange.

Yes. EdbMails OST to PST Converter holds onto every piece of email metadata, plus attachments and folder structures. Data integrity stays intact through the conversion — nothing gets stripped or scrambled.

Yes — EdbMails ships a demo/trial version of its OST to PST converter. The trial scans and previews the OST file contents, and exports up to 30 items per folder, covering emails, contacts, calendars, tasks, and the rest. That's enough to get a real feel for how the software handles your data before deciding whether to go to the full version for unlimited export.

EdbMails is built for speed on OST to PST conversions. The actual time it takes depends on a few moving parts though — OST file size, item count across emails, contacts, calendars, and tasks, the speed of your machine, and how complex the data structure is.

Yes — EdbMails saves OST data into multiple formats: EML, HTML, and MHT. Pick whichever fits the use case.

An OST (Offline Storage Table) file is a local copy of your mailbox sitting on your device, created when Cached Exchange mode is on in Outlook. The OST gives you offline access to mail when Exchange isn't reachable, and it syncs back up to the server once the connection's back. That sync is what keeps changes you made offline reflected in the actual Exchange mailbox.

A PST (Personal Storage Table) file is a different beast — it's a standalone file that holds your email data, contacts, calendar items, and the rest of your Outlook content. PSTs sit on your local device, which makes them easy to back up, copy across to another machine, or pull into a fresh Outlook install whenever you need to.

So in short — OST files exist for offline access to Exchange mailbox data; PST files exist for archiving and backup.

For more on this, see OST vs PST.

Yes — EdbMails OST converter handles recovery of corrupt or damaged OST files. The software pulls data out of OST files in most corrupted states and converts what it recovers into a working PST. Open that PST in Outlook and you're back to your data.

Yes — EdbMails provides 24/7 free technical support across the user base. The team's reachable through email, phone, and live chat for any OST to PST conversion issues. Remote access support is available too, which helps when the issue needs hands-on diagnosis. Support runs around the clock regardless of how complex the situation gets.

Offline OST files — the kind that have no Exchange connection anymore — convert into PST without any trouble. EdbMails reads the file directly off your drive, no live server connection needed.

Not at all. The conversion is fully independent of Exchange. EdbMails works with the OST file as a standalone source, so whether the original Exchange server is up, down, or gone entirely doesn't change what happens during the run.

One installer covers all three. EdbMails Setup bundles OST to PST, OST to Office 365, and OST to live Exchange into a single application — no separate downloads to chase, no different licenses for different destinations.

The PST files EdbMails generates are compatible with every Outlook version. Whichever version your team is on — current or older — the converted data opens without trouble.

Yes — you can preview OST file data before running the conversion. Once you've selected the OST file for recovery in EdbMails, the contents render in the interface. Click any folder in the tree view and the emails preview with the full headers — sender, recipient, subject, date — plus attachments. Calendar entries preview with their attributes (event date, time), and contacts show their details (name, email, phone number, and whatever else is on the record). The preview gives you a chance to verify the data is what you expect before committing to the conversion to PST.

No — EdbMails OST converter doesn't need the original Outlook profile to run the conversion. It's profile-independent.

EdbMails OST to PST converter makes transferring an OST file to a new computer straightforward. Convert the OST to PST first, then import the resulting PST into Outlook on the new machine. That gets your emails, contacts, and calendar items across cleanly without losing anything along the way.

 Steps to convert OST to PST from Outlook 2021, 2019, 2016 and 2013

The OST Recovery and Migration License is what you'll want for this. It covers the full workflow — pulling data out of inaccessible, corrupt, or damaged OST files and converting that data into PST — under one license rather than separate ones for each step.

The conversion runs entirely offline. Once EdbMails is installed and the OST file is on your machine, no internet connection comes into the picture — the whole run happens locally.

Yes — EdbMails OST to PST converter has an option to split large output PST files into smaller ones during conversion. The split is particularly useful for large OST sources, since it stops the resulting PST from getting unwieldy. Oversized PSTs slow Outlook down and increase the risk of file corruption. You set the size limit per PST, and EdbMails handles the division while keeping every mailbox item and the folder structure intact. The result holds up in Outlook even when the source OST is on the larger side.

Yes. The conversion writes into PST format, and that requires Outlook on the same machine with a configured profile

Encrypted OST files and password-protected ones both work. EdbMails gets through the protection on its own — you don't need the original password, and the conversion runs the same way it would on an unencrypted file.

No data is lost. The OST file you start with stays exactly as it was — EdbMails opens it for reading only, then writes the converted output to a brand new PST file. Both files exist independently afterward, with every folder, every attribute, and every mailbox item landing on the PST side in the shape it left the source.

Virtualized environments work the same way physical ones do. Whether the VM is running on VMware, Hyper-V, or a cloud-based Windows host, EdbMails behaves identically — no special install steps, no virtualization-specific settings to configure. The one thing to verify upfront is that the VM meets the application's minimum system requirements; everything else falls into place from there.

The folder hierarchy from the source OST carries straight into the PST — same nesting, same names, nothing rearranged. Whatever you had in Outlook before is what you'll find when you open the converted file.

There's no size cap. Small OSTs, large ones, the unusually big ones — all of them convert through the same workflow, with no different handling needed for size.

 Here's the fix for the 'Default Outlook profile.ost is in use and cannot be accessed' error.

Yes. The OST data stays readable even after the original profile has been deleted, gone orphan, or otherwise disconnected from its source. EdbMails pulls the data out of the file directly and converts it the same way it would for an active profile.

Advanced filters handle this. Date ranges, sender, recipient, subject, attachment names, read/unread status — set the criteria you want, and only the messages matching them go into the PST.