Large OLM files often cause freezing or incomplete conversion when using manual methods. GainTools OLM to MBOX Converter is designed to handle large OLM files safely without slowing down the system. It uses an optimized scanning process that easily processes heavy mailboxes while preserving emails, attachments & folders. It prevents losing any data or compromising during conversion. Even with oversized OLM files, it delivers accurate MBOX output quickly, making it an ideal solution for users dealing with large mailboxes. Moreover, try the free demo and experience real performance instantly on Windows.