Error uploading photos: Upload Failed (see details) -> File size error

Hi,

I have a brand new, private, family photo sharing site using ES 1.2.19 on Joomla 3.3.1. I tried creating a first album for a test, and selected quite a few (about 40) photos to upload, about 5MB each. 7 were uploaded succesfully and then I got the error Upload Failed (see details). When I clicked on see details I get File size error. Chrome console shows some JS errors in plupload.min.js:

{state: 1, runtime: "html5", features: Object, files: Array[0], settings: Object…}

Object {code: -600, message: "File size error.", file: plupload.File}

I have tried with Development and Uncompressed settings. I have tried with default Protostar template. Nothing works. I cannot add any more images to this album. See attached screenshot.

I use Amazon S3 for photo storage.

PHP 5.3.26