Why attach the same files to two different messages?
There is no logical reason for your VI to open up a Choose File dialog and ask for a zip file. There is only one function I can see in your VI that does anything with files, and that is the Express VI Write to Measurement File. Try taking that out of your program and see if it still pops up with file dialog for a zip file.
If the issue goes away, then it is some unexplainable issue with that express VI. IN which case I recommend getting rid of it and use regular file functions to save your data to the file.
