title: cygwin chmod and windows 7 file permission problems
body: <p>I've found a number of posts over the past several years on closely related topics.  However, I wonder if anyone has any specific advice for the following situation.</p>
  
  <p>I am a casual user of cygwin 2.4.0-1 on Win7 SP1.  I have used cygwin for many years on a variety of Win platforms.  Today, for the first time on this Win7 machine, I did a cygwin chmod 400 command on a single file, call it /cygdrive/c/some/folder/file.  What I then found was that Windows permissions had been altered, throughout C:, and not just in C:\some\folder.  Specifically, the Windows Properties dialog shows Read Only status for all folders in C:.  I can't write to my primary drive.  I have tried to change this using the Windows Properties dialog.  However, going back to Properties subsequently shows no change.  Rebooting the machine and again trying to update Properties through the dialog does not work.  Also, issuing chmod 770 from the cygwin command line did not help.</p>
  
  <p>I have been reading about differences in permissions handling, chmod vs. Win ACLs, permissions with respect to cygwin sshd specifically, and the use of Windows icacls and cacls, e.g. <a href="https://stackoverflow.com/questions/34575078/cygwin-chmod-777-command-made-other-users-access-denied-in-windows-7">Cygwin chmod 777 command made other users &#39;access denied&#39; in Windows 7</a></p>
  
  <p>I also added a file to /cygdrive/c/cygwin64/etc/fstab.d/ per:</p>
  
  <p><a href="https://stackoverflow.com/questions/4647752/cygwin-vim-windows-7-file-access-issue">Cygwin/vim Windows 7 file access issue</a></p>
  
  <p>which does not seem to help.</p>
  
  <p>Running icacls from the Windows command line on a couple of specific folders in C: shows the following:</p>
  
  <hr>
  
  <p>C:>icacls Folder</p>
  
  <p>Folder  BUILTIN\Administrators:(I)(F)
          BUILTIN\Administrators:(I)(OI)(CI)(IO)(F)
          NT AUTHORITY\SYSTEM:(I)(F)
          NT AUTHORITY\SYSTEM:(I)(OI)(CI)(IO)(F)
          BUILTIN\Users:(I)(OI)(CI)(RX)
          NT AUTHORITY\Authenticated Users:(I)(M)
          NT AUTHORITY\Authenticated Users:(I)(OI)(CI)(IO)(M)</p>
  
  <p>Successfully processed 1 files; Failed processing 0 files</p>
  
  <hr>
  
  <p>C:>icacls Users\user</p>
  
  <p>Users\user    NT AUTHORITY\SYSTEM:(OI)(CI)(F)
                BUILTIN\Administrators:(OI)(CI)(F)
                Machine\user:(OI)(CI)(F)
                Machine\HomeUsers:(RX)</p>
  
  <p>Successfully processed 1 files; Failed processing 0 files</p>
  
  <hr>
  
  <p>Anyway, before I start trying icacls commands that I don't fully understand, I was wondering if anyone here might have any specific advice for me.</p>
  
  <p>Many thanks,
  KCW</p>