wblachfo-
Posting your code (or a screenshot of it) is definately helpful, but here are a few things you might want to check:
-Make sure you are handling the errors (with a simple error handler or automatic error handling)
-Make sure you are sending non-void data into the express VI
-Doulbe check the file name field in the express VI or just use the prompt to choose the file location
We'll know more when we can see your code.
Xaq
