Hello we have an application schematics is this:

-Dropdownlist1 with postback enabled
On dropdownlist1 change event, dropdownlist2 is populated.

Execution flow is this:

Select one option on dropdownlist1, then autopostback-->populate dropdownlist2 on the basis of what you choose ondropdownlist1, in this way you choose operation to made on file.

You then select file on your pc in a fileupload1 in same page

Then you click a button on page, client upload file on server , server made some modification on file you have uploaded, server send back modified file to client with:

-response.writefile("filename")
-response.flush
-response.close

All works ok, but after client download file, if users change dropdownlist1 to select another operation,on page starts upload of file to server without clicking on button for uploading.


Seems something is chached/buffered from previous operation, and postback event send file upload.


How can i solve this unwanted file upoload?

No, no code in page load

Just declaration dbroot="filename"