>May have to do with the size of the blocks you feed into the encoding (and decoding) parts
>
>Base64 encoding : 3 bytes become 4 bytes (3 * 8 bits >> 4 * 6 bits)
>The block - if not a multiple of 3 bytes is padded with = or == see http://en.wikipedia.org/wiki/Base64
>
>To encode - feed blocks that are multiple of 3 bytes ( except the last block)
>
>
>What is the code to Encode and Decode ?

As this is Base64 encoded, I do not use to deal directly with bytes. So, basically, my initial approach was ok.

However, if I send 200,000 bytes at a time, this will not generate an error on the ConvertFromBase64() method I have. If I send 200,001 bytes at a time, for a divider by 3, this gives "Invalid length for a Base-64 char array.".