Random Error: images not adding to items! started over night

site was working 100% yesterday but today i went to add a new item attached an image and press privew and the image shows as missing link or broken.

the sites says image uploaded etc as normal but the image not working.

checked the server via ftp and the image file is there but the file size is 0

whats happening??

i have IH2 instaled and i tried clearing the cache etc but still no joy.

Also tried a different image and image format.... both jpg and gif fail!

when going to the image location in the browser the browser (ff) says it can not display image because it contains errors

Which site? What version of Zen Cart?

FIXED.... not sure what the problem is but it basically sorted its self out. Talked to my host and they were also scratching their heads as to why it wasn't working then was working 30 mins later.

We have gone throught all the files and downloaded all the changed files since last week and well the only new or changed files are image file from upload.... so meaning nothing has changed in the code of the site and nothing has got in and added hack files to my site either.......

putting it down the gremlins!