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Outlook
A family of Microsoft email and calendar products.
4,304 questions
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Hi @Sajish Sajayan
A .bak file in Outlook is a backup file created by the Inbox Repair Tool (scanpst.exe) when it repairs your Outlook data file (PST). It contains crucial data such as email messages, contacts, calendar items, and settings.
If the repair process is successful, you can safely delete the .bak file. However, if you're unsure or want to be extra cautious, you can keep it for a while longer just in case.
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