I was unable to upload files via FlashUpload option in Wordpress for quite some time now. It started happening after Adobe Flash 10 upgrade. I didn’t bothered much as there was an alternative right there on the screen. Today I got bit irritated thinking of one extra task required to get the work done. To eliminate this step, I immediately started digging for a fix at once. Solutions were right there on Wordpress forum. All I had to do is to download SWFUpload, extract it, and upload swfupload.swf in wp-includes/js/swfupload/ thats it. While I was applying this fix, I could see that Wordpress 7 had swfupload_f9.swf which was supported only by Flash 9. Okay, you’re done with it. Now start uploading the files with no issues.

flash_wp

Expecting this issue to be sorted out in upcoming version of Wordpress.

Reference links:

Flash Upload Not working in Latest 2.7 ver
Flash 10 and WordPress File Upload Problems