If you want a quick and free solution to Convert Microsoft OST files to PST format, then you can manual solution. But free tools convert limited OST files and risk of losing data.
So I highly suggest you attempt the most well-known software which is known as DataVare OST to PST Converter. It has several unique and technical features that are why it is gaining popularity with users. This program scans the entire OST file completely and shows a live view of all OST files and folders. Then simply convert the OST file to PST without wasting too much time or losing any data. And users can easily access their OST file in PST with complete data such as emails, contacts, calendars, journals, tasks, etc. If you have any doubts regarding the software's working process, then try its free trial version. which you can open a few OST files into Outlook PST files.
So I highly suggest you attempt the most well-known software which is known as DataVare OST to PST Converter. It has several unique and technical features that are why it is gaining popularity with users. This program scans the entire OST file completely and shows a live view of all OST files and folders. Then simply convert the OST file to PST without wasting too much time or losing any data. And users can easily access their OST file in PST with complete data such as emails, contacts, calendars, journals, tasks, etc. If you have any doubts regarding the software's working process, then try its free trial version. which you can open a few OST files into Outlook PST files.