issue with MIME Decode (Base64) for DOC/MHT files

[Dmitchell19]

Hello
I'm trying to use the standard MIME Encode/Decode (base 64) and notice that decoding from base64 to DOC/MHT seems to come up with corrupted files whereas PDF files seem to decode successfully.
To test this i set up a simple encode then decode process and found that it would encode to base64 but not decode correctly the resultant files
Do you know why this is the case? Is the something else i should be adding to the filter?
thanks