The Flash image upload function has stopped working on one of the sites I run. Whenever I try to upload an image it gives an 'HTTP error' and no further information.
This problem has arisen overnight following few if any changes to the site. I've tried deactivating any plugins I have installed or upgraded recently, with no effect.
I run another site on the same server and the Flash uploader works fine on it. The standard image uploader also works fine on both sites.
I have checked and I can upload images directly into the image directory via FTP.
I'm not sure how to progress with this problem, particularly as the error message is short and vague. There seems to be hundred of forum threads on it, many of which refer to earlier versions of WordPress and specific bugs that have been fixed.
Can anyone help?