Java Security

Whenever i go to decrypt a chunk of data, using RSA, i get the following exception thrown:

java.security.ProviderException: java.security.KeyException: The operation completed successfully.

this is a weird exception that i cannot find any information on, it happens at this line:

byte[] clearData = decipher.doFinal(chunk.getBytes());

here is the entire method:

public void signFile(File file, String infile)
  {
   
    try
    {
      Provider a[] = Security.getProviders();
      
      boolean hasCAPI = false;
      
      updateText("INSTALLED PROVIDERS:");
      for(int i = 0; i < a.length; i++) //display installed providers
      {
        System.out.println(a.toString());

updateText(a[i].toString());

if(a[i].contains("SunMSCAPI"))

hasCAPI = true;

}



if(!hasCAPI)

updateText("MSCAPI provider not found, breaking execution.");

else

{

updateText("MSCAPI provider found");



//String alias = "Peter Barkley's Encryption Certificate"; //"Peter Barkley's EFS Certificate";

updateText("Trying to open Windows-MY keystore using SunMSCAPI provider...");

KeyStore ks = KeyStore.getInstance("Windows-MY", "SunMSCAPI");

ks.load(null, null); //File, Char[] password



String alias = "";

Enumeration aliases = ks.aliases();

updateText("CERTS FOUND:");

while(aliases.hasMoreElements())

{

String aliasKey = (String)aliases.nextElement();

updateText(aliasKey);

if(aliasKey.contains("Encryption Certificate"))

{

updateText("Using Certificate: " +aliasKey);

alias = aliasKey;

}

}





Certificate c = ks.getCertificate(alias);

System.out.println("Alias: " +ks.getCertificateAlias(c));

System.out.println("Cert Type: " +c.getType());

updateText("Alias: " +ks.getCertificateAlias(c));

updateText("Cert Type: " +c.getType());

//System.out.println(ks.size()); //Number of certs in key store

PublicKey pubKey = (PublicKey) c.getPublicKey();

PrivateKey privKey = (PrivateKey)ks.getKey(alias, null);

KeyPair kp = new KeyPair(pubKey, privKey);



/*try{

c.verify(pubKey);

}

catch(Exception e){

updateText("Verify Public Key Error: " +e.getMessage());

e.printStackTrace();

}*/



if(privKey == null) //user did not sign into Entrust

{

updateText("Private key could not be gathered, probably due to bad entrust sign in");

System.out.println("Private key could not be gathered");

}



System.out.println("Private Key: " privKey "\n\nPublic Key: " +pubKey);

updateText("Private Key: " privKey "\n\nPublic Key: " +pubKey);



Cipher cipher = Cipher.getInstance("RSA");

cipher.init(Cipher.ENCRYPT_MODE, pubKey);



updateText("Encrypting: " +infile);



int len = infile.length();

int chunks = len/100;

int leftover = len - (chunks*100);

String leftoverString = infile.substring(len - leftover, len);

String finalCipherText = "";

//break into 100byte chunks and encrypt

for(int i = 0; i < chunks; i++)

{

String chunk = infile.substring(i*100, (i+1)*100);

byte[] cipherData = cipher.doFinal(chunk.getBytes());

int cipherlength = cipherData.length;

String ciphertext = new String(cipherData, 0, cipherlength);

//updateText("Chunk: " chunk  " ciphertext: " +ciphertext);

finalCipherText += ciphertext;



}



byte[] cipherData = cipher.doFinal(leftoverString.getBytes());

int cipherlength = cipherData.length;

String ciphertext = new String(cipherData, 0, cipherlength);

finalCipherText += ciphertext;



updateText("Encrypted text: " +finalCipherText);





//decrypt

Cipher decipher = Cipher.getInstance("RSA");

decipher.init(Cipher.DECRYPT_MODE, privKey);

len = finalCipherText.length();

chunks = len/100;

leftover = len - (chunks*100);

leftoverString = finalCipherText.substring(len - leftover, len);

String finalText = "";



for(int i = 0; i < chunks; i++)

{

String chunk = finalCipherText.substring(i*100, (i+1)*100);

byte[] clearData = decipher.doFinal(chunk.getBytes());

int clearlength = clearData.length;

String cleartext = new String(clearData, 0, clearlength);

finalText += cleartext;

}



byte[] clearData = decipher.doFinal(leftoverString.getBytes());

int clearlength = clearData.length;

String cleartext = new String(clearData, 0, clearlength);

finalText += cleartext;





updateText("Decrypted text: " +finalText);

}

}catch(Exception e){

updateText(""+e);

System.out.println(e.getMessage());

e.printStackTrace();

}

}
Any ideas on the decryption error?