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I have a BKS file that is around 20GB. How do I extract the MSSQL files from that?


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I didn't think BKS files contained the actual data, just a list of what data was to be backed up? – RobM Jun 4 '10 at 17:18
Thanks Robert. Thats what I thought too. But the BKS is 20GB so i suspect it has the data. – ServerDown Jun 4 '10 at 17:29

If the backup was created using ntbackup, you'd need to restore all or selected files from it using the Backup and Restore Wizard. If you trying to determine which files to restore, the SQL databases typically live in files with file extensions of MDF, LDF and NDF though that's not a requirement.

I'm not sure if ntbackup guarantees database consistency when doing backups, so it's possible the database would not restore cleanly.

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Thanks SqlACID. But I cant use the BKS file in the restore. the ntbackup only allows the BKF file to be selected for restoring. Any other way to extract data from BKS files? – ServerDown Jun 4 '10 at 17:06

I wonder if the backup was accidentally saved as a BKS file? A "real" BKS file would open in Notepad and be readable. You could try to open the file in Notepad and if it is human-readable, it doesn't contain your data. Else, you could change the extension to BKF and see if NTBackup will restore it.

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I have to agree with this. After all, what's the worse that can happen. – RobM Jun 4 '10 at 18:35
Notepad won't open a 20GB file, either use something like EditPad, or a hex editor (HxD is good). – Dentrasi Jun 4 '10 at 19:46
up vote 0 down vote accepted

It was actually a BAK file. Just run the standard restore database and point to the bks file.

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