Flash uploader was a nice way to upload multiple images at the same time. Unfortunately when Flash 10 was released, it stopped working. Therefore if a site has the ‘enable flash uploader’ option set to yes, the button does not work and therefor nothing happens when you click on it.
You need to go to the Global Configuration, System Tab and disable it.
This leaves you with the ability to just upload one file at a time. JCE has a nice image uploader that still allows you to choose multiple images. It can be downloaded here (I would recommend uninstalling JCE first and then installing the ‘Single installation package.’
The buttons don’t have that MS Office look that you may be used to with JoomlaFCK, but the image uploader has a lot of nice features and a great look. It also allows you to use the image button with the other wysiwyg buttons rather than going to the bottom. If you are a LDW client, we can set this up for you, just let us know if you’d like to try the switch.
Another option is to downgrade your Flash version to version 9 which for Windows, as of now you can still get here. Be sure to read the readme.html file, and I would recommend uninstalling flash 10 first. I haven’t tested this package yet as I am on an Ubuntu machine, so leave a comment if you try it.
Apparently we are not alone, other flash uploaders for other types of software also stopped functioning and Adobe knows about the issue, so hopefully the next version of Flash will have fixed this issue.

HI,
Simply use the Joomla Flash Uploader from http://www.tinywebgallery.com.
It works fine with flash 10 and has many more features as well.
- Michael