UnauthorizedAccessException Class

The exception that is thrown when the operating system denies access because of an I/O error or a specific type of security error.

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

[SerializableAttribute]
[ComVisibleAttribute(true)]
public class UnauthorizedAccessException : SystemException

The UnauthorizedAccessException type exposes the following members.

  NameDescription
Public methodSupported by the XNA FrameworkSupported by Portable Class LibraryUnauthorizedAccessException()Initializes a new instance of the UnauthorizedAccessException class.
Public methodSupported by the XNA FrameworkSupported by Portable Class LibraryUnauthorizedAccessException(String)Initializes a new instance of the UnauthorizedAccessException class with a specified error message.
Protected methodUnauthorizedAccessException(SerializationInfo, StreamingContext)Initializes a new instance of the UnauthorizedAccessException class with serialized data.
Public methodSupported by the XNA FrameworkSupported by Portable Class LibraryUnauthorizedAccessException(String, Exception)Initializes a new instance of the UnauthorizedAccessException class with a specified error message and a reference to the inner exception that is the cause of this exception.
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  NameDescription
Public propertySupported by Portable Class LibraryDataGets a collection of key/value pairs that provide additional user-defined information about the exception. (Inherited from Exception.)
Public propertySupported by Portable Class LibraryHelpLinkGets or sets a link to the help file associated with this exception. (Inherited from Exception.)
Public propertySupported by the XNA FrameworkSupported by Portable Class LibraryHResultGets or sets HRESULT, a coded numerical value that is assigned to a specific exception. (Inherited from Exception.)
Public propertySupported by the XNA FrameworkSupported by Portable Class LibraryInnerExceptionGets the Exception instance that caused the current exception. (Inherited from Exception.)
Public propertySupported by the XNA FrameworkSupported by Portable Class LibraryMessageGets a message that describes the current exception. (Inherited from Exception.)
Public propertySupported by Portable Class LibrarySourceGets or sets the name of the application or the object that causes the error. (Inherited from Exception.)
Public propertySupported by the XNA FrameworkSupported by Portable Class LibraryStackTraceGets a string representation of the immediate frames on the call stack. (Inherited from Exception.)
Public propertyTargetSiteGets the method that throws the current exception. (Inherited from Exception.)
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  NameDescription
Public methodSupported by the XNA FrameworkSupported by Portable Class LibraryEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodSupported by the XNA FrameworkSupported by Portable Class LibraryFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by the XNA FrameworkSupported by Portable Class LibraryGetBaseExceptionWhen overridden in a derived class, returns the Exception that is the root cause of one or more subsequent exceptions. (Inherited from Exception.)
Public methodSupported by the XNA FrameworkSupported by Portable Class LibraryGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetObjectDataWhen overridden in a derived class, sets the SerializationInfo with information about the exception. (Inherited from Exception.)
Public methodSupported by the XNA FrameworkSupported by Portable Class LibraryGetTypeGets the runtime type of the current instance. (Inherited from Exception.)

In XNA Framework 3.0, this member is inherited from Object.GetType().


In Portable Class Library Portable Class Library, this member is inherited from Object.GetType().
Protected methodSupported by the XNA FrameworkSupported by Portable Class LibraryMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodSupported by the XNA FrameworkSupported by Portable Class LibraryToStringCreates and returns a string representation of the current exception. (Inherited from Exception.)
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  NameDescription
Protected eventSerializeObjectStateOccurs when an exception is serialized to create an exception state object that contains serialized data about the exception. (Inherited from Exception.)
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An UnauthorizedAccessException exception is typically thrown by a method that wraps a Windows API call. To find the reasons for the exception, examine the text of the exception object's Message property.

UnauthorizedAccessException uses the HRESULT COR_E_UNAUTHORIZEDACCESS, which has the value 0x80070005.

The following example illustrates theUnauthorizedAccessException exception that is thrown when attempting to write to a read-only file.

using System;
using System.IO;

public class Example
{
   public static void Main()
   {
      string filePath = @".\ROFile.txt";
      if (! File.Exists(filePath))
         File.Create(filePath);
      // Keep existing attributes, and set ReadOnly attribute.
      File.SetAttributes(filePath, 
                        (new FileInfo(filePath)).Attributes | FileAttributes.ReadOnly);

      StreamWriter sw = null;
      try {
         sw = new StreamWriter(filePath);
         sw.Write("Test");
      }
      catch (UnauthorizedAccessException) {
         FileAttributes attr = (new FileInfo(filePath)).Attributes;
         Console.Write("UnAuthorizedAccessException: Unable to access file. ");
         if ((attr & FileAttributes.ReadOnly) > 0)
            Console.Write("The file is read-only."); 
       }
       finally {
         if (sw != null) sw.Close();
      }   
   }
}
// The example displays the following output: 
//    UnAuthorizedAccessException: Unable to access file. The file is read-only.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8

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