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AnswerUnknown user account

  • Monday, November 02, 2009 6:52 PMCoolAdi Users MedalsUsers MedalsUsers MedalsUsers MedalsUsers Medals
     
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    I have Windows7 RC on my system, earlier i had windows xp SP2. Recently i noticed an unknown user account (S-1-5-21-XXXXX......) in the security tab of few of the folders/files. But this user does not show up in the local user group in the control panel. Any idea what this account is and how to remove it?
     

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  • Wednesday, November 04, 2009 2:51 AMRobinson ZhangMSFT, ModeratorUsers MedalsUsers MedalsUsers MedalsUsers MedalsUsers Medals
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    Hi,

    @Cooladi Actually, this issue is caused by File system ACLs(Access Control List) on the harddisk, but since the account is deleted it can't be resolved to a username.

    You can try to use Microsoft Utility Tool (SubInACL ) to remove them.

    @Joesync Maybe a software/service sets a specific user account on these pic files, after changing OS or remove this user account on the computer, they also cannot be resolved.

    Hope it helps.

     

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  • Tuesday, November 03, 2009 8:24 AMRobinson ZhangMSFT, ModeratorUsers MedalsUsers MedalsUsers MedalsUsers MedalsUsers Medals
     
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    Hi Cooladi, 

    It is user account on previous Windows XP SP2. You can simply remove it in ssecurity tab. First, please take ownership of the folder/file if necessary. Then, click Edit, choose unknown ID, click Remove.

    Hope it helps.
     
  • Tuesday, November 03, 2009 6:19 PMCoolAdi Users MedalsUsers MedalsUsers MedalsUsers MedalsUsers Medals
     
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    Robinson, Thanks for the reply. There are too many folders/file that have this unknown user, is there any way to remove this user at system level instead of folder/file level. I tried removing at the drive level, but its still there. Any registry update/deletion would do the trick?

    Also why did this user exist on the system in the first place, i did a fresh install of Windows7 RC and on the same system partition that previously had XP, just curious!!
     
  • Tuesday, November 03, 2009 6:39 PMJoesync Users MedalsUsers MedalsUsers MedalsUsers MedalsUsers Medals
     
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    I found this thread searching for the same thing.

    I noticed all my Image files in documents/pictures have this unknown user when you go to properties>security. It only has Read permission. I checked some other files and didnt see it, but it may exist on others. I thought it was just weird that it was on all the pictures. Doesnt make sense at all, why would this errornous user be a part of the system?

    This is a fresh install of windows 7 64. Retail

    I has vista 64 on teh disk before this

     
  • Wednesday, November 04, 2009 2:51 AMRobinson ZhangMSFT, ModeratorUsers MedalsUsers MedalsUsers MedalsUsers MedalsUsers Medals
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    Hi,

    @Cooladi Actually, this issue is caused by File system ACLs(Access Control List) on the harddisk, but since the account is deleted it can't be resolved to a username.

    You can try to use Microsoft Utility Tool (SubInACL ) to remove them.

    @Joesync Maybe a software/service sets a specific user account on these pic files, after changing OS or remove this user account on the computer, they also cannot be resolved.

    Hope it helps.