javascript - 302 error when uploading file with SWFUpload in firefox -

i using swfupload upload images. shows error 302 in firefox. uploads fine chrome.

          upload1 = new swfupload({     // backend settings     upload_url: "/articles/photos.aspx?foldername=" + foldername,       // file upload settings     file_size_limit: "1024*5", // 5mb     file_types: "*.bmp; *.gif; *.jpeg; *.jpg; *.png;",     file_types_description: "image files",     file_upload_limit: "10",     file_queue_limit: "0",      // event handler settings (all handlers in handler.js file)     file_dialog_start_handler: filedialogstart,     file_queued_handler: filequeued,     file_queue_error_handler: filequeueerror,     file_dialog_complete_handler: filedialogcomplete,     upload_start_handler: uploadstart,     upload_progress_handler: uploadprogress,     upload_error_handler: uploaderror,     upload_success_handler: uploadsuccess1,     upload_complete_handler: uploadcomplete,     // button settings     button_image_url: "../images/xpbuttonuploadtext_61x22.png",     button_placeholder_id: "spanbuttonplaceholder1",     button_width: 61,     button_height: 22,     // flash settings     flash_url: "/swfuploader/swfupload.swf",       custom_settings: {         progresstarget: "fsuploadprogress1",         cancelbuttonid: "btncancel1"     },      // debug settings     debug: false }); 

i not sure causing error..