error. file not fully uploaded

[nena]

when i try to upload an image i get:

Error
File was not fully uploaded.

i believe the error is caused by the index.php which generates the gallery, but i can't find which point causes it. i edited little things in it like how the comments show up and how dates are printed. plus i added a counter.

here's the whole index.php code:
http://www.milkandme.net/error.txt

[raminia+]

maybe the file was larger than the maximum uploadable file on your server.