The code can be found at: http://pastebin.com/3Yg5bHra
My problem is, that when I decrypt then nothing gets returned at all. Nothing gets decrypted.
It goes wrong somewhere around line 111-114. The cryptoStream (csDecrypt) is empty, eventhough I put data into the memorystream (msDecrypt)
EDIT Nudier came up with a solution
Remember to set the key for Encryption and Decryption and also de IV(Initialization Vector)