keep getting upload php $_FILES error = 3 (partially uploaded)

Question

I am using dropzone extension for Yii framework to upload some files by registered users. Everything working well but some users for some files that they trying to upload it

Answer 1

As php documentation says, this error is

UPLOAD_ERR_PARTIAL is given when the mime boundary is not found after the file data. A possibly cause for this is that the upload was cancelled by the user (pressed ESC, etc).

Also there are some more variants to check:

1. Permissions are wrong (i doubt, cause it will break all users).

2. Not enough free space on server.

3. This error occures when uploading from iOS.

4. This error can occure when uploading folder (due to browser limitations). On Mac OSX it occures 100%.

So this is possible errors to check. Hope this will help.