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Can you please provide me a link to the project where you are getting this error message

I got the same error last night - I was attempting to upload some .hex files and a BOM.xlsx. I had not seen it before.

i got the same error after trying to edit http://www.instructables.com/id/Valentines-Day-Motion-Activated-LED-Heart/ which was published from an iphone

Can you provide me a link to the project where you are getting this error message please. What happens when you start a new project and save?