Repairing permissions after windows reinstall

Henry S. Thompson
Fri Jul 1 13:36:00 GMT 2016

Andrey Repin writes:

> Greetings, Henry S. Thompson!
>> 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.
> So, what? Go to top directory properties, Advanced, Owner tab, Change, and
> change the owner to what is desired.

Much to glib an answer.  Changing the owner is the _last_ thing you want
to do after (programmatically) changing a bunch of ACLs.

>> 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?

> If you write these SID's it would be easier to tell.

...-513 - Domain User, it turns out.

>> Can this be easily fixed, i.e. put me back where I used to be?
> As Corinna said, this can be fixed, you just have to fake a valid UID for old
> user to jumpstart the process.
> Obviously, you would need to run the script as administrator account to work
> on the permissions changes.

Script is non-obvious, will share once I have mostly debugged it.

       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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