For a large OLM file, the best method is usually to use an OLM to PST converter that supports bulk processing, large files, and PST splitting. For example, SysInfo OLM Converter lets users add a single large OLM file or multiple OLM files and preview the mailbox contents before starting the conversion. After selecting the required mailbox items, users can choose PST as the destination and begin the conversion. If the resulting PST becomes too large, the software provides an option to divide it into smaller PST files based on the required size. This can be useful when the OLM contains years of emails, attachments, contacts, calendars, or other mailbox information. The tool also keeps the source folder structure intact, so the converted PST remains organized rather than placing all the data into a single location.
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