SP2010 - Central Admin - "An Unexpected Error Has Occurred" (handle is invalid)
Problem Summary:
SharePoint Administrators lost the ability to browse successfully to Central Admin on a SharePoint 2010 server
Errors:
1) In the browser: An Unexpected Error Occurred
2) In the ULS Log: w3wp.exe 0x15EC SharePoint Foundation Runtime Unexpected System.Runtime.InteropServices.COMException: The handle is invalid. (Exception from HRESULT: 0x80070006 (E_HANDLE)) 2fce79ff-3aed-440c-b4f7-78fa5d7a10d5
3) Process Monitor: “BAD IMPERSONATION”
Root Cause
Application of a Group Policy to the OU that includes the WFE removed the IIS_IUSRS group from the local security policy on the server for the user right assignment of “Impersonate a client After Authentication.” The IIS_IUSRS group needs the ability to impersonate clients after authentication because this is how the SharePoint/IIS Application Pool impersonates the SharePoint Administrator who is trying to reach Central Admin.
Recommended Solution:
The local group IIS_IUSRS needs to be allowed to be listed in the Impersonate a Client After Authentication right. Please work with your Active Directory Administrator and/or Security teams to determine what needs to happen in Group Policy to make sure the Central Admin servers (or even all WFEs) have this.
Applies to:
SharePoint 2010 and IIS 7.0
References:
KB 981949 shows that the IIS_IUSRS group is supposed to (by default) have the Impersonate right.
https://support.microsoft.com/kb/981949 - Description of default permissions and user rights for IIS 7.0 in Windows Server 2008
https://learn.iis.net/page.aspx/140/understanding-built-in-user-and-group-accounts-in-iis/ - Understanding Built-In User and Group Accounts in IIS 7
Understanding the New IIS_IUSRS Group