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I have just reinstalled a PC with Windows 7 RTM (previously was RC).

The PC had a second hard disk, with various permissions set for the two local user accounts.

After reinstalling the two user's SIDs obviously no longer exist, so they show up as unknown SIDs in the folder security permissions tab.

I would like to know if there is a standard technique or utility/script to allow me to basically scan over the hard disc and update all old SIDs to new SIDs (assuming I know which SID belonged to who), so I don't have to manually reset all the permissions.

Thanks, Jack

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up vote 1 down vote accepted

You should be able to use icacls.exe to replace all instances of one SID with another:

C:\Users\reubeno>icacls /?
ICACLS directory [/substitute SidOld SidNew [...]] /restore aclfile
                 [/C] [/L] [/Q]
    applies the stored DACLs to files in directory.
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