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eSoftTools OST to PST Converter software. You can resolve the error "Outlook OST files are not in use and cannot be accessed." It is completely secure and risk-free for your device. All software can be operated smoothly by all users, technical and non-technical. It supports all Windows operating systems, including Windows 11 versions. Try the software once for a free demo version and save 25 things from various folders in your OST mailbox.
More info - Fix error Outlook OST file in use and cannot get accessed