Repairing permissions after windows reinstall

Henry S. Thompson
Tue Jun 28 11:45:00 GMT 2016

Corinna Vinschen writes:

> On Jun 28 11:04, Henry S. Thompson wrote:
>> Good news: My cygwin file tree survived a Windows (10) reinstall
>> Not-so-good news: I have a new SID, so not only do I not own those files
>> any more (that's easily fixed), but I don't have the permissions I
>> should, because they are now held by some miscellaneous old SID.
>> In fact I see _two_ raw SIDs when I look at the security tab for any
>> directory in the old cygwin tree: one has Full control, and the other
>> just Read & execute.
>> I presume the first is the old me, what's the second?
>> Can this be easily fixed, i.e. put me back where I used to be?
> Off the top of my head, what you could do is this:
> - Generate an /etc/passwd entry for your old user SID by hand.
>   Make sure to use an arbitrary weird UID like 98765.
> - Exit and start an elevated shell.
> - find . -uid 98765 | xargs chown <newuser name or UID>
> Analog for the group if necessary.

Thanks, but ownership is not the problem.  The problem is that the ACLs
(as reported by Windows itself via the Security tab) don't allow the new
me (or OWNER) the necessary (or indeed any) permissions, those are given
to the old SID.

Here's what shows up for /bin:

Advanced Security Settings for bin
Name: C\C64\bin
Owner: ht (LUTHER\ht) ' Change
Permission entries:
Type Principal                         Access       lnherite... Applies to
Allow S-1-5-21-32...-1001 Full control None This folder only
Allow S-1-5-21-32...-513  Read & ex... None This folder only
Allow Everyone            Read & ex... None This folder, subfolders and files
Allow CREATOR OWNER       Full control None Subfolders and files only
Allow CREATOR GROUP       Read & ex... None Subfolders and files only

       Henry S. Thompson, School of Informatics, University of Edinburgh
      10 Crichton Street, Edinburgh EH8 9AB, SCOTLAND -- (44) 131 650-4440
                Fax: (44) 131 650-4587, e-mail:
 [mail from me _always_ has a .sig like this -- mail without it is forged spam]

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