Event ID - 9551

Event Id9551
SourceMSExchangeIS Public Store
DescriptionAn error occurred while upgrading the ACL on folder [Public Folders]/%2AACL_LOG_TEST located on database "First Storage Group\Public Folders". The Information Store was unable to convert the security for /O=MICROSOFT/OU=MATRIX/CN=TEST_PF/CN=PF_ACL into a Windows 2000 Security Identifier. It is possible that this is caused by latency in the Active Directory Service, if so, wait until the user record is replicated to the Active Directory and attempt to access the folder (it will be upgraded in place). If the specified object does NOT get replicated to the Active Directory, use the Microsoft Exchange System Manager or the Exchange Client to update the ACL on the folder manually. The access rights in the ACE for this DN were 0x41b.
Event InformationAn event ID 9551 that is generated by the information store may be logged incorrectly if a public folder contains a non-printable character or invalid Hypertext Transfer Protocol (HTTP) characters (for example, *, %, ^, and so on). The incorrect logging varies depending on the character that is used.
This problem can occur because non-printable characters (invalid HTTP characters) are converted to valid ones. The information store converts these characters to % followed by the ASCII equivalent, so that the folders can be addressed by Uniform Resource Locator (URL). For example, a folder that is called *testfolder is converted to %2Atestfolder (2a is the ASCII equivalent of *). However, the Windows 2000 Event Viewer uses the %# sign as a delimiter when viewing events. Therefore, events that contain %# as "arguments" make the Event Viewer log incorrect. 
To work around this problem, use valid HTTP characters to create folders. 
Microsoft has confirmed that this is a problem in Microsoft Exchange 2000 Server.
Reference LinksHow to troubleshoot public folder performance issues that are related to ACL conversions in Exchange 2000 and in Exchange 2003

Exchange 2000 Event ID 9551 Is Logged Incorrectly View products that this article applies to.

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