Excel in web browser, not asking to save on exit

[Fatauto]

I have an Excel sheet that I run from a website. Clicking the link open the sheet up in a new window. When the new window is closed a message box pops up and says "Document has been modified, do you want to save changes"

I tried to add code that does not promp the user to save on close, did not work.

I also tried to add a button to close excel, button does nothing in webpage.

Any ideas how to close the page without asking to save it?

thanks, Adam