Resolving Account Unknown


When going through the security permissions on some of the objects in AD seeing some Account Unknown(S-1-5-21-*). My question is how can i resolve these to readable account names so i can find out whether there is a purpose to having these in there.

Easiest way possible would be great.

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it appears like that because the user account with that SID was deleted.
You can only delete it (or ignore).

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fcaatAuthor Commented:
i understand that ... but is there not a app that you can use to resolve the SID ... this would help in letting me know whether or not i still need the permissions there.
you cannot find because it doesn't exist any more
surely you won't need it :)
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fcaatAuthor Commented:
i know there is a way you can resolve sids to common names. i am not sure how to do it though. that is the question that i asked.
map000Commented: for exemple
there are 2 tools named sid2user and user2sid
as map000 sayd, you cant resolve deleted accounts.
these tools are only for active user accounts.
if you give access for a user, his sid is entered in the access list of the directory/file.
if you delete this user, it will not delete this entry in the access list.
this is what you are seeing.
non of this tools will give you an account for this sid.
If the user account has been deleted, there will be no mapping to a common name - thus, your SID entry.

Two reasons you see this are because a user account was added directly to an ACL on an object instead of using groups.  By assigning permissions to groups you eliminate this problem.


If the SID cannot resolve to a name due to network issues - an example is a user from another domain and for some reason it cannot contact the PDC for that domain to resolve it's common name.

fcaatAuthor Commented:
is there any way to find out what the sid was ... can you translate the sid even if the user account has been deleted. Just so you can know for sure whether or not its a network issue or just the user has been deleted.
If you use LDP.exe you can look at the Tombstoned objects as long as they are less than 60 days old.  It's pretty hardcore, but you should be able to at least look for it.

Here is how:;en-us;284928

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Windows Server 2003

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