PST (Personal Storage Table) is Microsoft Outlook's file format for storing emails, calendar events, contacts, and other Outlook data locally.
OST (Offline Storage Table) is Microsoft Outlook's cached mailbox format for offline access to Exchange server data.
Reach for PST when your priority is email archiving, outlook backup and migration — 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.
Convert PST files to OST online for free. High-quality conversion with no registration required.
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.pst,.PST (max 100MB)
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PST files store Outlook data as a local archive file, typically used for backup, archival, and offline access to mailbox data outside an Exchange server environment. However, some Outlook workflows require data in the offline storage format used by Exchange cached mode.
OST is Outlook Offline Storage Table, the format Exchange uses for cached mailbox data during disconnected operation. Converting PST to OST allows archived mail data to be reintegrated into Outlook's cached mode, syncing with Exchange when connectivity is restored.
Yes, GoConvertFile offers free conversion of PST to OST for files up to 100MB. No registration required.
Most PST 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 PST to OST conversion depends on the content complexity and quality settings. Both formats use similar compression approaches so sizes are comparable.