Upload error - The file could not be written to disk

[eluser]TheFuzzy0ne[/eluser]
That error is actually a PHP error, not anything to do with CodeIgniter as such. There error is [url="http://uk3.php.net/features.file-upload.errors"]UPLOAD_ERR_CANT_WRITE[/url].

The obvious reason for it not working is that the permissions or not set correctly, so I'd suggest you check the directory really is writeable by trying to create a blank file in there with PHP, or using is_really_writable().

Another reason might be your allowed Web quota. If you're nearing the limit, you may not be able to write to the disk.