Free tool for converting OST to PST?

you can convert ost files in to pst files by using different tools some of these are outlook 2016  and office 365 etc..

• You can convert OST to PST by using different tools and methods, but simply free method steps are given below:
•  Go to Files >Open & Export and click Import & Export.
• Select Export to a file; then click Next.
• Select the second option—Outlook Data File (.pst)—and click Next.
• Select the folder which you want to export and click Next.
• Browse the location where you want to save the new PST file and choose the options regarding the duplicate items. 

There is an automated tool like Kernel for OST to PST Converter to Convert OST File to PST.

1. Open Outlook and go to the File menu.
2. Select the Import/Export option.
3. Choose Export to a file.
4. Select Outlook Data File (.pst)
5. Choose whether to export a specific folder or the whole account.
6. Check the Include subfolders box.
7. Next, select a destination for the Export, and then click Finish.

Export Exchange OST PST Access to e-mails from OST software files currently after revival of Exchange as well as optimize offline file storage Retained file formats Storage then Outlook user with no problem in Microsoft Outlook version. MS Outlook add-on wishes to achieve unsolicited emails from OST files then exploit can not open OST file explain to repair corrupt OST files and restore and format PST file then without open complicatedness in MS Outlook. Exchange OST Converter to PST tool supports all MS Outlook version 97, 98, 2000, XP, 2003, 2007 and 2010 and also works on all versions of Windows operating system such as Windows 9X / ME / NT / 2000 / XP / Vista / The user will download the trial version of this program to try this process, after trying to get the desired user result then buy the full version $ 99 only. More information exposed

1. Export Mailbox as a PST File

   Login to Outlook with the Exchange account that was used to create the OST files. And to export the OST mailboxes to PST, follow the simple procedure as given here:

   1. Go to Files >Open & Export and click Import & Export

   2. Select Export to a file; then click Next.3. Select the second option—Outlook Data File (.pst)—and click Next4. Select the folder(s) which you want to export and click Next.5. Browse the location where you want to save the new PST files and choose an option regarding the duplicate items.
2. Use Archiving to Save OST Emails to PST By enabling the Auto Archive method in Outlook, you will be able to save the items of the OST file in a separate PST file. This method helps you to keep the size of your mailbox manageable. When there are many older messages and you do not require them in the mailbox, you can put them in the archive folder easily. This will reduce the size of the mailbox. Follow the simple steps to enable auto archiving in Outlook.
   1. Launch the Outlook application, go to File and click Options.
   2. Go to Advanced and click Auto Archive Settings
   3. Now select the number of days in which you want to run auto archiving. Select the folder to save the archived file; also, provide the archiving options and finally click OK.

OST to PST Converter Tool is one of the superior software that helps to restore the emails from an OST file and convert them into new Outlook PST file format with all email properties.

If the OST file is already connected to Outlook, it can be directly exported to PST using Outlook ( no need for any tool ).

For orphan OST file, there is no free version available. All tools convert limited number of emails to PST in free version.