Hi All, System is a VMware ESX W2k8 Sp2 server with Exchange 2007 Sp2 incl. update roll up 4. Exchange role is Hub Transport. (same on a VM machine with Client Access) In the App Event log some times a large amount of Error 513 is logged. Log Name: Application Source: Microsoft-Windows-CAPI2 Date: 27.07.2010 03:38:22 Event ID: 513 Task Category: None Level: Error Keywords: Classic User: N/A Computer: EXH02.domain.com Description: Cryptographic Services failed while processing the OnIdentity() call in the System Writer Object. Details: AddCoreCsiFiles : BeginFileEnumeration() failed. System Error: Access is denied. Any Ideas?Stephan

Hi, Please try the steps below: This problem occurs if NTFS permissions have been removed to the C;\WINDOWS\WINSXS\FILEMAPS directory and / or files. Did a process monitor and found that we're receiving an access is denied on $$.cdf-ms (this is the first file) other files can be the cause of the problem too. To resolve this issue please run the following command from an administrative CMD prompt: Takeown /f %windir%\winsxs\filemaps\* /a icacls %windir%\winsxs\filemaps\*.* /grant "NT AUTHORITY\SYSTEM:(RX)" icacls %windir%\winsxs\filemaps\*.* /grant "NT Service\trustedinstaller:(F)" icacls %windir%\winsxs\filemaps\*.* /grant BUILTIN\Users: (RX) Have a look into this article : http://support.microsoft.com/kb/2009272 Ripu Daman Mina | MCSE 2003 & MCSA Messaging

Ripu, thank you for your quick reply. I will test this solution. But why do somne machines have this problem and some not?Stephan