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.mbox,.MBOX (max 100MB)
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MBOX is a platform-agnostic, text-based mailbox format used by Unix systems and open-source clients like Thunderbird. While universally readable, MBOX files cannot integrate with Outlook's cached Exchange mode, which requires data in the proprietary OST binary format.
OST is Outlook Offline Storage Table, the format that enables Outlook to cache Exchange mailbox data for offline access. Converting MBOX to OST allows email archives from open-source clients to be integrated into Outlook's cached mode for seamless online-offline email access.
Yes, GoConvertFile offers free conversion of MBOX to OST for files up to 100MB. No registration required.
Most MBOX to OST conversions complete within seconds for standard-sized files. Larger files may take longer depending on the conversion complexity.
OST is ideal for exchange offline cache, outlook data recovery. Outlook OST - Offline Storage Table for cached mailbox data
File size after MBOX to OST conversion depends on the content complexity and quality settings. Both formats use similar compression approaches so sizes are comparable.
MBOX is a generic mailbox format that stores all email messages concatenated in a single text file, commonly used for email archiving and migration.
OST (Offline Storage Table) is Microsoft Outlook's cached mailbox format for offline access to Exchange server data.
Reach for MBOX when your priority is email migration, cross-platform email backup — its uncompromising quality ensures every detail is preserved.
Reach for OST when your priority is exchange offline cache, outlook data recovery — its uncompromising quality ensures every detail is preserved.