EncryptedData.Decrypt method

Article
03/22/2021

[CAPICOM is a 32-bit only component that is available for use in the following operating systems: Windows Server 2008, Windows Vista, and Windows XP. Instead, use Platform Invocation Services (PInvoke) to call the Win32 API functions CryptEncryptMessage and CryptDecryptMessage to encrypt and decrypt messages. For information about PInvoke, see Platform Invoke Tutorial. The .NET and CryptoAPI via P/Invoke: Part 1 and .NET and CryptoAPI via P/Invoke: Part 2 subsections of Extending .NET Cryptography with CAPICOM and P/Invoke may also be helpful.]

The Decrypt method decrypts an encrypted and encoded data string. The resulting plaintext data becomes the Content property of the EncryptedData object. Decryption of the content fails unless the secret, set by the SetSecret method, is exactly the same as the secret used to derive the key used to encrypt the content.

Syntax

EncryptedData.Decrypt( _
  ByVal EncryptedMessage _
)

Parameters

EncryptedMessage [in]: String that contains the encoded, encrypted data to be decrypted.

Return value

This method does not return a value.

Remarks

The session key derived from the current secret is used for the decryption. This method will not produce the correct plaintext unless the current secret exactly matches the secret used to encrypt the message.

Requirements

Requirement	Value
End of client support	Windows Vista
End of server support	Windows Server 2008
Redistributable	CAPICOM 2.0 or later on Windows Server 2003 and Windows XP
DLL	Capicom.dll