This documentation is archived and is not being maintained.

MutexAuditRule Class

Represents a set of access rights to be audited for a user or group. This class cannot be inherited.

Namespace:  System.Security.AccessControl
Assembly:  mscorlib (in mscorlib.dll)

public sealed class MutexAuditRule : AuditRule

The MutexAuditRule class is one of a set of classes that the .NET Framework provides for managing Windows access control security on named system mutexes. For an overview of these classes and their relationship to the underlying Windows access control structures, see MutexSecurity.


Windows access control security is meaningful only for named system mutexes. If a Mutex object represents a local mutex, access control is irrelevant.

To get a list of the audit rules currently applied to a named mutex, use the Mutex.GetAccessControl method to get a MutexSecurity object, and then use its GetAuditRules method to obtain a collection of MutexAuditRule objects.

MutexAuditRule objects do not map one-to-one with access control entries in the underlying discretionary access control list (DACL). When you get the set of all audit rules for a mutex, the set contains the minimum number of rules currently required to express all the access control entries.


The underlying access control entries change as you apply and remove rules. The information in rules is merged if possible, to maintain the smallest number of access control entries. Thus, when you read the current list of rules, it might not look exactly like the list of all the rules you have added.

Use MutexAuditRule objects to specify access rights to be audited for a user or group. To apply a rule to a named system mutex, use the Mutex.SetAccessControl method to get the MutexSecurity object. Modify the MutexSecurity object by using its methods to add the rule, and then use the Mutex.SetAccessControl method to reattach the security object.

Important noteImportant Note:

Changes you make to a MutexSecurity object do not affect the access levels of the named mutex until you call the Mutex.SetAccessControl method to assign the altered security object to the named mutex.

MutexAuditRule objects are immutable. Security for a mutex is modified using the methods of the MutexSecurity class to add or remove rules; as you do this, the underlying access control entries are modified.


Security on synchronization objects is not supported for Windows 98 or Windows Millennium Edition.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0