<div>
Try adding the user to a group that has access to the folder. That's generally the best way to give users permissions. Remove them from the group when they don't need access.
</div>


<div>
It is usually because the SID is not resolvable from your domain controller. &nbsp;Check your communications path to your domain controller from the server (Firwall perhaps running in strict mode). &nbsp;You can check the communications path by using portquery or portqueryUI for a GUI.<br />
<br />
<a href="http://www.microsoft.com/download/en/details.aspx?id=24009" rel="ugc">http://www.microsoft.com/d<wbr />ownload/en<wbr />/details.a<wbr />spx?id=240<wbr />09</a><br />
<br />
Also, try removing the unresolvable SID, clicking apply then ok, then re-adding the user back to the share.
</div>


<div>
Number-1:<br />
<br />
&nbsp; Thank you for the quick response. &nbsp;I've already tried that (sorry I didnt' include in my orignal post). &nbsp;I thought that would clear up the problem too.
</div>


<div>
tech:<br />
<br />
&nbsp; The communication path is umimpeded. &nbsp;The firewall is allowing clear communication between server and DC. &nbsp;I've already removed and re-added the unresolved SID more times than I can count. &nbsp;I think I've narrowed it down to a replication problem between AD's
</div>


<div>
Evidently the 2 servers are not synching up properly. I presume that the 2008 DC is acting like a 2003 DC for co-existence.<br />
<br />
I would suspect the logon server for the machine you are using to apply privileges. Possible to reboot?
</div>


<div>
 &nbsp;No, unfortunately there is no way for me to reboot until after 8 p.m. &nbsp;We are located at a 24x7 facility. &nbsp;I'll try the suggestion as soon as it's possible to do so. &nbsp;Thanks 
</div>


<div>
kshays,<br />
Thanks for your help! &nbsp;Upon review of the dcdiag report, I discovered the FrsEvent wasn't passing its test.<br />
I applied the solution offered by Microsoft and all seems to be working great. &nbsp;Thanks again.
</div>


<div>
Good deal pyizzle.<br />
<br />
Glad I could help you out there. &nbsp;That along with netdiag is a really good starting point when troubleshooting AD and DNS related issues.<br />
<br />
Thanks,<br />
<br />
Kevin
</div>


<div>
<div class="content wysiwyg-content">
I've recenlty needed to lock down the permissions on a certain folder on my network. &nbsp;A user joined my company and needs access to this folder. &nbsp;I created an account in AD and added that account into the needed folders permissions tab with full control. &nbsp;I apply the changes and close the dialog box. &nbsp;I open the dialog box again (within 5 seconds of closing) and the account is now an &quot;Account Unknown (SID #)&quot;<br />
<br />
We have two DC's (Windows 2K3 amd 2K8) with no outside trusts. &nbsp;I've verified the time sync between the two have been able to log onto our network with the new user's account. &nbsp;The only problem lies in applying permissions to folder's. &nbsp;Any help would be greatly appreciated.
</div>
</div>


I've recenlty needed to lock down the permissions on a certain folder on my network.  A user joined my company and needs access to this folder.  I created an account in AD and added that account into the needed folders permissions tab with full control.  I apply the changes and close the dialog box.  I open the dialog box again (within 5 seconds of closing) and the account is now an "Account Unknown (SID #)"

We have two DC's (Windows 2K3 amd 2K8) with no outside trusts.  I've verified the time sync between the two have been able to log onto our network with the new user's account.  The only problem lies in applying permissions to folder's.  Any help would be greatly appreciated.

Account Unknown when adding user to folder permissions

Operating system security (OS security) is the process of ensuring OS integrity, confidentiality and availability. OS security refers to specified steps or measures used to protect the OS from threats, viruses, worms, malware or remote hacker intrusions. OS security encompasses all preventive-control techniques, which safeguard any computer assets capable of being stolen, edited or deleted if OS security is compromised, including authentication, passwords and threats to systems and programs.

OS Security

Active Directory (AD) is a Microsoft brand for identity-related capabilities. In the on-premises world, Windows Server AD provides a set of identity capabilities and services, and is hugely popular (88% of Fortune 1000 and 95% of enterprises use AD). This topic includes all things Active Directory including DNS, Group Policy, DFS, troubleshooting, ADFS, and all other topics under the Microsoft AD and identity umbrella.