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Exception when initializing private key from xml string (RSACryptoServiceProvider using FromXmlStrin

Posted By:      Posted Date: September 15, 2010    Points: 0   Category :.NET Framework
Hi, I'm trying to create a private key using the following code segment   System.Security.Cryptography.AsymmetricAlgorithm key = new System.Security.Cryptography.RSACryptoServiceProvider();string privateKeyXml = File.ReadAllText(fullPathPrivateKey);key.FromXmlString(privateKeyXml);   It does work with .NET Framework 3.5 SP1 on Windows XP, but when I try to run it on .NET Framework 4.0 on Windows 7 I get the following exception ((System.Security.Cryptography.RSACryptoServiceProvider)(key)).CspKeyContainerInfo.Exportable' threw an exception of type 'System.Security.Cryptography.CryptographicException', with message "Key does not exist". Full stack trace is shown below: System.Security.Cryptography.CryptographicException: Key does not exist. at System.Security.Cryptography.CryptographicException.ThrowCryptographicException(Int32 hr) at System.Security.Cryptography.Utils._GetProviderParameter(SafeProvHandle hProv, Int32 keyNumber, UInt32 paramID) at System.Security.Cryptography.CspKeyContainerInfo.get_Exportable() Does anyone have a clue to why this doesn't work on .NET 4.0? Regards, Simon

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