Knowledge Base

Maximum number of ACEs in an ACL

Article ID: 166348

Article Last Modified on 12/1/2007

APPLIES TO

This article was previously published under Q166348

SYMPTOMS

When you add users or groups to the security permissions of an object share, file, or directory, you may receive the following error message:
You have exceeded the operating system's limit on the number of users and groups that can be in a security information structure. Remove some users or groups and try the operation again.
When you use Cacls.exe to perform this function, you may receive the following error message:
The parameter is incorrect.

CAUSE

This issue occurs when you reach the maximum size of the access control list (ACL). The size of an ACL varies with the number and size of its access control entries (ACEs). The maximum size of an ACL is 64K, or approximately 1,820 ACEs. However, for performance reasons, the maximum size is not practical.

MORE INFORMATION

For more information about how security descriptors and access control lists work, visit the following Microsoft Web site:

http://technet2.microsoft.com/WindowsServer/en/Library/9c7bc921-2517-4e7a-ba39-d37c8b8202e31033.mspx?mfr=true


Additional query words: max permission user group unexpected inconsistent unusual ace

Keywords: kbprb KB166348


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