Generate Excel

I am using the code below to create an excel document from data that is returned from an sql query. The formatting of the excel document is pretty and all is good unless I hit the back button and run my query a second time, or a third time (I haven't made it past 3
times). Basically what happens is every time I do this, excel does not close once I hit my back button. Does anyone have a solution to this problem? Another problem is that when I run the query it just opens excel within my browser, is there any way to make it ask if you want to save or open the file?

I basically throw this code at the top of the html doc: .....