[C#]
    TElCustomCryptoContext DecryptInit(int Algorithm, int Mode, TElCustomCryptoKey Key, TElCPParameters Params, TSBProgressFunc ProgressFunc, Object ProgressData);
    TElCustomCryptoContext DecryptInit(byte[] AlgOID, byte[] AlgParams, int Mode, TElCustomCryptoKey Key, TElCPParameters Params, TSBProgressFunc ProgressFunc, Object ProgressData);

[VB.NET]
    Function DecryptInit(ByVal Algorithm As Integer, ByVal Mode As Integer, ByVal Key As TElCustomCryptoKey, ByVal Params As TElCPParameters, ByVal ProgressFunc As TSBProgressFunc, ByVal ProgressData As Object) As TElCustomCryptoContext
    Function DecryptInit(ByVal AlgOID As Byte(), ByVal AlgParams As Byte(), ByVal Mode As Integer, ByVal Key As TElCustomCryptoKey, ByVal Params As TElCPParameters, ByVal ProgressFunc As TSBProgressFunc, ByVal ProgressData As Object) As TElCustomCryptoContext

[Pascal]
    function DecryptInit(Algorithm : integer; Mode : integer; Key : TElCustomCryptoKey; Params : TElRelativeDistinguishedName = nil; ProgressFunc : TSBProgressFunc = nil; ProgressData : pointer = nil) : TElCustomCryptoContext; virtual; abstract;
    function DecryptInit(const AlgOID : ByteArray; const AlgParams : ByteArray; Mode : integer; Key : TElCustomCryptoKey; Params : TElRelativeDistinguishedName = nil; ProgressFunc : TSBProgressFunc = nil; ProgressData : pointer = nil) : TElCustomCryptoContext; virtual; abstract;

[C++]
    TElCustomCryptoContextHandle DecryptInit(int32_t Algorithm, int32_t Mode, TElCustomCryptoKey &Key, TElRelativeDistinguishedName &Params, TSBProgressFunc pMethodProgressFunc, void * pDataProgressFunc, void * ProgressData);
    TElCustomCryptoContextHandle DecryptInit(int32_t Algorithm, int32_t Mode, TElCustomCryptoKey *Key, TElRelativeDistinguishedName *Params, TSBProgressFunc pMethodProgressFunc, void * pDataProgressFunc, void * ProgressData);
    TElCustomCryptoContextHandle DecryptInit(const std::vector<uint8_t> &AlgOID, const std::vector<uint8_t> &AlgParams, int32_t Mode, TElCustomCryptoKey &Key, TElRelativeDistinguishedName &Params, TSBProgressFunc pMethodProgressFunc, void * pDataProgressFunc, void * ProgressData);
    TElCustomCryptoContextHandle DecryptInit(const std::vector<uint8_t> &AlgOID, const std::vector<uint8_t> &AlgParams, int32_t Mode, TElCustomCryptoKey *Key, TElRelativeDistinguishedName *Params, TSBProgressFunc pMethodProgressFunc, void * pDataProgressFunc, void * ProgressData);

[PHP]
    TElCustomCryptoContext DecryptInit(integer $Algorithm, integer $Mode, TElCustomCryptoKey $Key, TElRelativeDistinguishedName $Params, TSBProgressFunc|callable|NULL $ProgressFunc, TSBPointer|array of byte|string|NULL $ProgressData)
    TElCustomCryptoContext DecryptInit(array of byte|string|NULL $AlgOID, array of byte|string|NULL $AlgParams, integer $Mode, TElCustomCryptoKey $Key, TElRelativeDistinguishedName $Params, TSBProgressFunc|callable|NULL $ProgressFunc, TSBPointer|array of byte|string|NULL $ProgressData)

[Java]
    TElCustomCryptoContext decryptInit(int arg0, int arg1, TElCustomCryptoKey arg2, TElCPParameters arg3, TSBProgressFunc arg4, TObject arg5);
    TElCustomCryptoContext decryptInit(byte[] arg0, byte[] arg1, int arg2, TElCustomCryptoKey arg3, TElCPParameters arg4, TSBProgressFunc arg5, TObject arg6);