I've had the the same problem in uploading images for several days. It doesn't work for any image format and any size. I am using windows 7 with Firefox.

Could you please try again? I've shortened up the list of allowed extensions by a few, and I can now properly upload without issue with FF on Windows. (Also remember - if you are uploading with the flash uploader enabled, you can always just drag a file onto the Reply text box to upload too).

 

Yes, it works perfectly now. Thanks for the help!

 

The problem happened again.
http://i.imgur.com/aqIYhgo.png

 

I couldn't upload any image with any size. I gave the error in the image above. I am using Firefox. Please help.