I also wanted to migrate my Outlook OST to PST but I did not find any software that could migrate my OST file to PST without damaging it. Then my friend advised me to use eSoftTools OST to PST Converter Tool, which I used and its features are really very good. I also tried its free demo first.
You can easily migrate Outlook OST file to PST with the professional tool like Yota OST to PST Converter tool. I recently used this tool to Convert my Outlook OST to PST with all attachments and data elements. This tool Quickly convert multiple OST files to PST in a single attempt. This also provide the preview mode during migration. I highly impressed with this tool's working.
To migrate Outlook OST to PST, you can use the manual method by opening Outlook with the original profile and going to File > Import/Export > Export to a file > Outlook Data File (.pst)this works only if the OST is accessible. However, if the OST file is orphaned or corrupted, or the profile is unavailable, a reliable option is using the MSOutlookHelp OST to PST Converter, which allows quick and secure conversion of OST files without needing Outlook. Ive personally used it during a system crash, and it helped recover all my emails smoothly. You can check it here: www.msoutlookhelp.com/ost-to-pst-converter.html.