English
日本の
PCVITA software to convert offline and orphaned Outlook OST files without Exchange
OST Converter Tool
PCVITA OST Converter converts offline, orphaned and corrupt OST files from Outlook 2019, 2016, 2013, 2010, 2007, 2003 and 2000 into 14 formats, PST, EML, MSG, MBOX, HTML, NSF, PDF, vCard and CSV among them. OST converter software opens the file without Exchange Server, an Outlook profile or a live mailbox, keeps folders and attachments in place and removes S/MIME or OpenPGP encryption. Free demo previews every item and exports 10 items per folder.
- Input
- Offline, orphaned or damaged OST files from Exchange, Office 365 and IMAP accounts, any size
- Output
- PST, MBOX, EML, MSG, EMLX, NSF, PDF, HTML, MHT, TXT, DOC, CSV, vCard and ICS
- Converts
- Emails, contacts, calendars, tasks, notes, journals and attachments with the folder tree
- Needs
- No Exchange Server, no Outlook profile and no admin rights on the Windows machine
Encrypted emails open with the certificate or key, Search All Drives finds every OST file on the machine and a date filter limits the export to the period you need. See all features. For a damaged OST file with deleted items to bring back, open the OST Recovery Software.
How OST Converter Tool Converts an Offline OST File
Your OST file goes in on one side, whether Outlook still opens it or not. Mailbox items come out on the other, in one of 14 formats, with folders and attachments in place.
Outlook OST File
Exchange, Office 365 or IMAP account, Outlook 2000 to 2019
- Offline OST from a working Outlook profile
- Orphaned OST after the account or server went away
- Corrupt OST or an Outlook.bak copy from a scan
PCVITA OST Converter
Works on your Windows machine, no Exchange or Outlook login
- Quick scan or Advance scan
- 8 preview views before the export
- Email encryption removed with the key
14 Output Formats
Email formats and document formats, one export job per format
- PST, MBOX, EML, MSG, EMLX and NSF for mail clients
- PDF, HTML, MHT, TXT, DOC and CSV for records
- vCard for contacts and ICS for calendars
- 1AddSelect one OST file or search a drive for every data file on it.
- 2ScanChoose Quick or Advance scan and preview the items in 8 views.
- 3ExportExport every item or only ticked ones in the format you need, with filters.
Convert Your OST File in 6 Steps
Six screens from Add File to the export report. Click a step for its screen. Open the Software Guide for the settings of every single format.
Step 1. Add the OST File
Install OST Converter Tool on Windows and open it. Click Add File. Outlook does not need to be open. Even the account that created the file does not need to exist any more.
Step 2. Select or Search the File
Choose Select File and browse to the OST file or the Outlook.bak file. Choose Search File with Search Selected Drive or Search All Drives instead. OST converter then lists the OST and BAK files it finds.
Step 3. Choose the Scan Mode
Select Quick for a healthy or lightly damaged OST file. Select Advance when Quick shows no data or the file is highly corrupted. Add the S/MIME certificate or OpenPGP key here if the emails are encrypted, then click Add.
Step 4. Preview the Mailbox Items
Save the scan report when the scan completes so a second session loads faster. Folders with data appear in bold and deleted items appear in red. Open an email in Normal Mail, Hex, Properties, Message Header, MIME, HTML, RTF or Attachments view, then move between the Mail, Calendar, Contacts, Tasks, Notes and Journal tabs.
Step 5. Select the Export Format
Click Export to convert every item or Export Selected for the ticked ones. Select PST, MSG, EML, HTML, MBOX, PDF, vCard, EMLX, NSF, TXT, ICS, MHT, Documents or CSV. Open Advanced Settings for the split, date filter, categories and naming options.
Step 6. Set the Destination and Export
Use Browse to choose the destination folder. Keep Maintain Folder Hierarchy ticked or untick it and choose Don’t Export Empty Folders. Click Export, wait for 100 percent and save the report as CSV.
No licence needed for the demo. Preview every item and export 10 from every folder.
OST Converter Software Features
Every option of PCVITA OST Converter, grouped by the job you came here for.
Converts OST Files to 14 Formats Without Outlook
One OST file goes in and any of 14 formats comes out, one job per format. You need no Exchange profile, no IMAP login and no Outlook installation for the conversion itself.
Six Email Formats
Export OST to PST for Outlook, MBOX for Thunderbird, EMLX for Apple Mail, NSF for HCL Notes and EML or MSG for single messages.
Eight Document Options
Save emails as PDF, HTML, MHT or TXT files or as DOC, DOCX and RTF documents, contacts as vCard or CSV and calendars as ICS files.
No OST File Size Limit
Convert an OST file above 2 GB, 20 GB or 50 GB in one job. Input size is not capped.
Exchange, Office 365 and IMAP OST Files
OST converter opens the offline file of an Exchange, Office 365 or IMAP account and treats every one the same way.
Standard User Account and 20 Languages
Convert as a standard or guest Windows user without admin rights, with the interface in English, French, German, Spanish or 16 other languages.
Converts Orphaned and Corrupt OST Files Too
Outlook needs the account and the server to open an OST file. OST converter software needs only the file.
Orphaned OST File Conversion
Convert the OST file of a deleted mailbox, a removed account or a decommissioned Exchange Server without reconnecting to the server or rebuilding a profile.
Corrupt OST and Outlook.bak Files
Advance scan opens a damaged OST file or the Outlook.bak copy a scan utility left behind and exports what it finds, with deleted items marked in red.
Remove S/MIME and OpenPGP Encryption
Tick Remove Encryption and add the S/MIME certificate or OpenPGP private key, password included. Converted emails then open as plain mail.
Search Every Drive for OST Files
Search Selected Drive or Search All Drives lists every OST and BAK file on the machine with its path, so several files load in one session.
Save the Scan Report
Save the scan once and the OST file converter loads the scanned file again in a later session without a second scan.
Previews Every Item Before the Export
Check what the OST file holds, item by item, then decide on the format and the filters.
8 Preview Views
Switch an email between Normal Mail, Hex, Properties, Message Header, MIME, HTML, RTF and Attachments views with one click.
Tabs for Every Item Type
Mail, Calendar, Contacts, Tasks, Notes and Journal tabs show one item type at a time, with the folder list beside them.
Folders With Data in Bold
Folders with data appear in bold and empty folders stay plain, so you know before the export which folders carry items.
Attachments in the Preview
Attachments tab lists every file attached to the selected email and shows it in the lower right pane.
Export Only What You Tick
Tick single emails, contacts or calendar entries and click Export Selected to convert those items only.
Filters and Settings for Every Output Format
Advanced Settings on the export screen shape the output before the job starts.
Split the Output PST by Size
Set a size in GB and OST to PST conversion produces several smaller PST files instead of one oversized file.
Date Filter and Categories
Enter a start and end date or several ranges and tick mails, contacts, calendars, tasks, journals or notes for the export.
Naming Convention for Single Files
Name MSG, EML, HTML, PDF and other single files by subject, by subject and date or another pattern you select.
PDF Page Layout and Bates Numbers
Set margins from 2 to 10 mm, portrait or landscape, A3, A4 or Letter paper and header or footer text. Add a Bates number with a date stamp for legal exports.
Folder Hierarchy and CSV Report
Keep Maintain Folder Hierarchy on to mirror the source tree or switch it off with Don’t Export Empty Folders. Success and fail counts save as a CSV report.
Test every option on your own OST file. Free demo shows every item and exports the first 10 in a folder.
Why Outlook Cannot Open or Export an Orphaned OST File
Four facts from Microsoft pages that explain the gap and what PCVITA OST converter software does about it.
- 1
OST Files are Copies Tied to a Server
Microsoft describes the offline Outlook Data File as a copy of the items saved on the mail server, created when an Exchange account works in Cached Exchange Mode. Once the account or the server is gone, Outlook has nothing to sync against and will not open the file on its own. PCVITA OST Converter opens the file as it stands.
- 2
Outlook Export Needs a Connected Account
Outlook exports to a .pst file from an account that is added to Outlook and has finished downloading mail. Microsoft’s own fix for an OST that will not open is to delete the file and let Outlook download the data again from Exchange Server. OST converter software needs no connection and no download.
- 3
ScanOST is Gone and the Repair Page Says Recreate
Microsoft removed the OST Integrity Check tool (ScanOST.exe) from Outlook 2010 and later. Its Repair Outlook Data Files page tells Exchange users to delete the .ost file and let Outlook recreate it on the next start. PCVITA tool converts the OST or its BAK copy with a Quick or an Advance scan instead.
- 4
Local Items Not on the Server Need an Export First
One exception to the rebuild advice sits on Microsoft Learn. Local data that is not present on the server must go to a .pst file before the OST is deleted. When Outlook will not open, that export never happens. PCVITA OST Converter exports those items as PST or 13 other formats.
Prepare Before Using the OST Converter Tool
Seven checks before the first conversion. Go through them once and keep the list for the next file.
- Copy the OST file with Outlook closed to a working folder. Outlook lists the path on the Data Files tab of Account Settings. Search All Drives finds the file when you do not know the path.
- Close Outlook before you add the file. Outlook keeps the OST locked while it is open. Some other Office programs do the same. Locked files show an in use message.
- Install Microsoft .NET Framework 4.5 or later on a Windows machine with 100 MB free disk space and 512 MB RAM, 1 GB recommended.
- Keep certificates and private keys at hand, with their passwords, when the OST holds encrypted emails.
- Decide the output format before the job. One export job produces one format, so a PST for Outlook and a PDF set for records are two separate jobs.
- Install Outlook only for the Use Outlook option on the PST export screen. Conversion, preview and the other 13 formats need no Outlook.
- Try the free demo on your own OST file first. Download the OST Converter Tool demo, check the preview and export 10 items from any folder.
System needs come from the Specifications table below. Outlook behaviour comes from the Microsoft pages in the Sources list.
OST Converter Software Pricing
Start with the free demo, buy one licence when the preview shows what you need. Every option is in both editions, only the export count differs.
Demo Edition
Free
Preview every item, export 10 from every folder
- Export limit10 items in every folder
- FeaturesAll
- LicenceNot needed
Version 10.0, 85 MB, Windows
Full Edition
$49 one licence
Export every item from every OST file you load
- Export limitNone
- FeaturesAll
- DeliveryActivation key by email
30 Days Money Back*, Safe & Secure checkout
Included in Both Editions Same options in the demo and the full edition
- Add One or Several OST Files
- Quick and Advance Scan Modes
- Orphaned, Offline and Damaged OST Files
- S/MIME or OpenPGP Decryption
- Preview Panel With 8 Views and Item Tabs
- 14 Email and Document Export Formats
- Split, Date Filter, Categories and Naming
- Folder Hierarchy and CSV Export Report
OST Converter Tool Specifications
Version, Windows needs, input and output in two short tables.
| Version | 10.0 |
|---|---|
| File size | 85 MB |
| Windows versions | Windows 11, 10, 8.1, 8, 7, Vista and 2000 (32 and 64 bit), Windows Server 2003, 2008 and 2012 |
| Prerequisite | Microsoft .NET Framework 4.5 or later |
| Hardware | 1 GHz processor (2.4 GHz recommended), 512 MB RAM (1 GB recommended), 100 MB free hard disk space |
| Interface languages | English, French, Japanese, Portuguese, Spanish, Chinese, German, Italian, Russian, Indonesian, Dutch, Danish, Hungarian, Norwegian, Polish, Swedish, Turkish, Vietnamese, Czech and Thai |
| Free demo limit | Preview of every item, export of 10 items a folder in every format |
| Delivery | Download link and activation key by email after payment confirmation |
| Input files | Offline, orphaned or corrupt OST files of Exchange, Office 365 and IMAP accounts plus the Outlook.bak file from ScanOST or ScanPST |
|---|---|
| Outlook versions | Outlook 2019, 2016, 2013, 2010, 2007, 2003 and 2000 |
| Exchange versions | Exchange Server 2003 to 2019, every release in between |
| Items converted | Emails, contacts, calendars, tasks, notes, journals and attachments |
| Scan modes | Quick scan and Advance scan (deep scan for a highly corrupted file, 64 bit Windows) |
| Output formats | PST, MSG, EML, HTML, MBOX, PDF, vCard, EMLX, NSF, TXT, ICS, MHT, Documents (DOC, DOCX, RTF) and CSV |
| Export options | Split PST by size, date range, categories, naming convention, Maintain Folder Hierarchy, Don’t Export Empty Folders, CSV export report |
| Outlook installation | Not needed, except for the Use Outlook option on the PST export screen |
OST Converter Tool vs Outlook Export to PST
Outlook’s own export wizard next to PCVITA tool, so you know which route fits your OST file.
| Point | Outlook Export to PST | PCVITA Tool |
|---|---|---|
| Needs | Account added to Outlook with its mail downloaded | OST file alone, no Exchange and no profile |
| Orphaned OST file | Not opened. Outlook recreates the .ost from the server only when the account connects | Converted as it stands after the mailbox or server is gone |
| Damaged OST file | Delete and download again is Microsoft’s route. ScanOST is not in Outlook 2010 and later | Quick or Advance scan opens the damaged file or its BAK copy |
| Output | PST only | 14 email and document formats |
| Selection | Folders selected in the wizard | Ticked items, folders, date ranges and categories |
| Encrypted emails | Stay encrypted | Encryption removed with the certificate (S/MIME) or the private key (OpenPGP) |
| Large output | One PST file | Output PST split by size in GB |
| Price | Included with Outlook | Free demo, full edition $49 |
Outlook export facts come from Export or backup email, contacts and calendar to an Outlook .pst file (Microsoft Support) and Open or import items from an offline Outlook Data File (.ost) (Microsoft Support). ScanOST facts come from Synchronization problems occur in Outlook and in Outlook Web App (Microsoft Support). PCVITA tool facts come from the Specifications and Features sections of this page.
What an OST File Holds Before You Convert It
- Cached Exchange Mode keeps a copy of the mailbox on the computer. By default 12 months of email is available offline, so older mail stays on the server when the offline window was left at the default.
- New Outlook for Windows has no Cached Exchange Mode, so it creates no OST file. OST converter works with files from classic Outlook.
- Microsoft recommends a backup of the data file before any repair tool touches it. Copy the OST first and convert the copy.
- Local items that never reached the server exist only in the OST. Export them before anyone deletes or rebuilds the file.
- Deleted items the file still holds appear in red after Advance scan. For deep recovery of a badly damaged file, the OST Recovery Software is the better fit.
Open the Software Guide for the export settings of every format, PST split size and PDF page layout included.
Sources for OST Conversion Facts Microsoft pages behind the Outlook facts on this page
- Microsoft SupportOpen or import items from an offline Outlook Data File (.ost)
- Microsoft SupportCached Exchange Mode in Outlook
- Microsoft SupportExport or backup email, contacts and calendar to an Outlook .pst file
- Microsoft SupportSynchronization problems occur in Outlook and in Outlook Web App
- Microsoft LearnSynchronization issues between Outlook and Outlook Web App
- Microsoft SupportRepair Outlook Data Files (.pst and .ost)
OST Converter Tool FAQs
What users ask before they convert an OST file, in three groups.
Working and Limits How the converter behaves during the job
How does the OST Converter Tool convert an OST file?
Six steps convert one OST file.
- Step 1. Open PCVITA OST Converter and click Add File.
- Step 2. Select the OST or BAK file or search a drive for it.
- Step 3. Choose Quick or Advance scan and click Add.
- Step 4. Preview the folders and items in 8 views.
- Step 5. Click Export or Export Selected and select one of 14 formats.
- Step 6. Browse to the destination, click Export and save the CSV report.
Can I convert an orphaned OST file when the Exchange account no longer exists?
Yes. PCVITA OST Converter opens an orphaned OST file without the mailbox, the server or the Outlook profile that created it. Add the file, scan it and export the items in any of the 14 formats.
Does the OST converter need Outlook or an Exchange connection?
No. OST converter software opens the file on its own, with no Exchange Server, IMAP login or Outlook profile. Outlook on the machine is needed only for the Use Outlook option on the PST export screen.
Can OST converter software convert a corrupt OST file?
Yes. Select Advance scan for a damaged OST file or the Outlook.bak copy and export what the scan finds. For a badly damaged file where deleted items matter most, the OST Recovery Software is built for that job.
Is there an OST file size limit for the conversion?
No. PCVITA OST Converter converts OST files above 2 GB, 20 GB or 50 GB without a size cap. Split the output PST by size when the target Outlook version needs smaller files.
How long does an OST file take to convert?
Conversion time depends on the file size, the item count and the scan mode. Quick scan on a healthy file finishes faster than Advance scan on a corrupt one, so start the job and keep the machine on until the report appears.
Can I convert several OST files at once?
Yes. Choose Search File in the Add File window, then Search Selected Drive or Search All Drives. Every OST and BAK file found appears in a list. Tick the files you need and they convert in one session.
How do I open the converted PST file in Outlook?
Open it as a data file or import it. In Outlook select File, Open & Export, Open Outlook Data File and browse to the converted PST. Outlook then shows the PST as a folder set in the folder pane. Import/Export under the same menu merges the items into an existing mailbox instead.
Demo and Price Demo limits and the full edition price
What does the free demo of the OST converter do?
Every option, with an export cap. Demo edition adds OST files, scans them, previews every item in 8 views and exports 10 items per folder in any of the 14 formats.
How much does the full edition of the OST converter cost?
$49 for one licence. Full edition removes the 10 item folder limit, comes with a 30 day money back guarantee and sends the activation key by email after payment.
Compatibility and Formats Outlook, Exchange and Windows versions, formats and encryption
Which Outlook and Exchange versions does the OST converter support?
Outlook 2019, 2016, 2013, 2010, 2007, 2003 and 2000 on the Outlook side. Exchange Server 2003 to 2019 on the server side, plus OST files of IMAP and Office 365 accounts.
Which Windows versions does OST converter software support?
Windows 11, 10, 8.1, 8, 7, Vista and 2000 in 32 and 64 bit, with Windows Server 2003, 2008 and 2012. Needs on the machine are Microsoft .NET Framework 4.5 or later, a 1 GHz processor, 512 MB RAM and 100 MB of disk space.
Which formats can the OST converter export to?
14 formats. Email formats are PST, MSG, EML, MBOX, EMLX and NSF. Document formats are PDF, Documents (DOC, DOCX and RTF), HTML, MHT, TXT, CSV, vCard and ICS. One export job produces one format, so repeat the job for a second format.
Can the tool decrypt S/MIME or OpenPGP encrypted OST emails?
Yes, with the certificate or the private key. Tick Remove Encryption, select the encryption type and add the S/MIME certificate or the OpenPGP private key with its password. Exported emails then open as plain mail.
Does OST converter software keep the folder structure and attachments?
Yes. Maintain Folder Hierarchy mirrors the source tree in the output. Attachments stay with their emails in PST, MSG, EML, MBOX, EMLX and NSF exports. Email properties and RTF or HTML formatting stay intact. PDF export pins, appends or saves attachments as separate files.
Another question? Open Live Chat or write to us on the Contact Us page.
OST Converter Tool Reviews
Star ratings submitted on pcvita.com, with four customer notes about their OST conversion.
I had an orphan OST file whose data was required to be accessed immediately. The OST file conversion application did wonders for me. It miraculously converted orphaned OST file within a few minutes. Also, this amazing OST export tool is easy to use and understand.
Handling a team of 200 members is not an easy task for me ever. Using Exchange Server network helped me to streamline communication flow but due to its sudden crash, I really got tensed. Then, OST converter came to my notice. Really a brilliant piece by development team!
OST file converter helped me in adding OST file to Outlook 2013 with such an ease. It is a very economical and efficient solution for offline Outlook OST file conversion. Kudos to the development team for developing this exceptional software.
Changing an OST file into some other format was a nightmare for me but, thanks to this OST Converter for helping me out from this tedious task. The conversion is superfast and what I like the most about this product is that it converts all types of OST including offline, corrupt, damage, orphan files.
GearDownload: 100% clean badge, no spyware, adware or viruses found in PCVITA software.
DownloadAtoZ: 5 star award badge for PCVITA software. See every badge on the PCVITA awards page.
Key Takeaways on OST File Conversion
Five lines that sum up the page.
- Files and versions: converts offline, orphaned and damaged OST files from Outlook 2000 to 2019, with no size limit and no Exchange profile.
- 14 formats: PST, MBOX, EML, MSG, EMLX and NSF for mail clients, PDF, HTML, MHT, TXT, DOC and CSV for records, vCard and ICS for contacts and calendars.
- Preview and filters: 8 email views and item tabs, then date range, categories, split PST and naming options before the export.
- Encryption: locked emails export as plain mail once you add the certificate or the private key.
- Demo and price: free demo exports 10 items from every folder, one $49 licence removes the cap and a 30 day money back guarantee covers it.
Convert Your OST File Without Exchange or Outlook
Start with the free demo. Add the OST file, check every item in the preview and export 10 from any folder, then buy the full edition for the rest.
Safe & Secure · 30 Days Money Back*